SEC Form 424B5 filed by Soluna Holdings Inc.

Filed Pursuant to Rule 424(b)(5)

Registration No. 333-286638

PROSPECTUS SUPPLEMENT

(To Prospectus dated April 29, 2025)

Up to $3,750,000

Common Stock

On April 29, 2025, we entered into a certain At the Market Offering Agreement, or Sales Agreement, with H.C. Wainwright & Co., LLC, or Wainwright, relating to shares of our common stock, par value $0.001 per share (“common stock”), offered by this prospectus supplement and the accompanying prospectus. In accordance with the terms of the Sales Agreement, we may offer and sell shares of our common stock having an aggregate offering price of up to $3,750,000 from time to time through Wainwright.

Our common stock is listed on the Nasdaq Capital Market under the symbol “SLNH”. The last reported sale price of our common stock on April 28, 2025 on the Nasdaq Capital Market was $0.82.

Sales of our common stock, if any, under this prospectus may be made in sales deemed to be “at the market offerings” as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, or the Securities Act, including sales made directly on or through the Nasdaq Capital Market, the existing trading market for our common stock, or any other existing trading market in the United States for our common stock, sales made to or through a market maker other than on an exchange or otherwise, directly to Wainwright as principal, in negotiated transactions at market prices prevailing at the time of sale or at prices related to such prevailing market prices if authorized by us in writing, and/or in any other method permitted by law. Wainwright is not required to sell any specific number or dollar amount of securities, but will act as a sales agent using commercially reasonable efforts consistent with its normal trading and sales practices, on mutually agreed terms between Wainwright and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

The compensation to Wainwright for sales of common stock sold pursuant to the Sales Agreement will be equal to 3.0% of the gross proceeds of any shares of common stock sold under the Sales Agreement. In connection with the sale of the common stock on our behalf, Wainwright will be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of Wainwright will be deemed to be underwriting commissions or discounts. We have also agreed to provide indemnification and contribution to Wainwright with respect to certain liabilities, including liabilities under the Securities Act or the Exchange Act of 1934, as amended, or the Exchange Act. See the section titled “Plan of Distribution” on page S-8 of this prospectus supplement. This offering pursuant to this prospectus supplement and the accompanying prospectus will terminate upon the earlier of (a) the sale of shares of our common stock pursuant to this prospectus supplement and the accompanying prospectus having an aggregate sales price of $3,750,000, or (b) the termination by us or Wainwright of the Sales Agreement pursuant to its terms.

As of the date of this prospectus supplement, the aggregate market value of our outstanding common stock held by non-affiliates, or the public float, was $11,343,898, which was calculated based on 10,601,774 outstanding common stock held by non-affiliates at a price of $1.07 per share, the closing price of our common stock on March 17, 2025, as reported on the Nasdaq Capital Market. Pursuant to General Instruction I.B.6 of Form S-3, in no event will we sell shares pursuant to this prospectus with a value of more than one-third of the aggregate market value of our common stock held by non-affiliates in any 12-month period, so long as the aggregate market value of our common stock held by non-affiliates is less than $75,000,000. During the 12 calendar months prior to, and including, the date of this prospectus, we have not sold any securities pursuant to General Instruction I.B.6 of Form S-3.

Investing in our common stock involves risks. See “Risk Factors” beginning on page S-5 of this prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

H.C. Wainwright & Co.

April 29, 2025

TABLE OF CONTENTS

PROSPECTUS Supplement

PROSPECTUS

ABOUT THIS PROSPECTUS Supplement

This prospectus supplement and the accompanying prospectus are part of a shelf registration statement that we filed with the U.S. Securities and Exchange Commission, or the SEC, utilizing a “shelf” registration process. This document is in two parts: (i) this prospectus supplement, which describes the specific terms of this offering and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference herein and (ii) a shelf registration statement on Form S-3 (File No. 333-286638) that the SEC declared effective on April 29, 2025. Generally, when we refer to this prospectus, we are referring to all parts of this document combined. To the extent there is a conflict between the information contained in this prospectus supplement and the information contained in the accompanying prospectus or any document incorporated by reference therein filed prior to the date of this prospectus supplement, you should rely on the information in this prospectus supplement; provided that if any statement in one of these documents is inconsistent with a statement in another document having a later date, for example, a document incorporated by reference in the accompanying prospectus, the statement in the document having the later date modifies or supersedes the earlier statement.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

You should rely only on the information contained in this prospectus supplement or the accompanying prospectus, or incorporated by reference herein. We have not authorized, and the Placement Agent has not authorized, anyone to provide you with information that is different. The information contained in this prospectus supplement or the accompanying prospectus, or incorporated by reference herein or therein is accurate only as of the respective dates thereof, regardless of the time of delivery of this prospectus supplement and the accompanying prospectus or of any sale of our common stock. It is important for you to read and consider all information contained in this prospectus supplement and the accompanying prospectus, including the documents incorporated by reference herein and therein, in making your investment decision. You should also read and consider the information in the documents to which we have referred you in the sections entitled “Where You Can Find More Information” and “Incorporation of Certain Information by Reference” in this prospectus supplement and in the accompanying prospectus, respectively.

We are offering to sell, and seeking offers to buy, the securities offered by this prospectus supplement only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the accompanying prospectus and the offering of the securities offered by this prospectus supplement in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement and the accompanying prospectus must inform themselves about, and observe any restrictions relating to, the offering of our common stock and the distribution of this prospectus supplement and the accompanying prospectus outside the United States. This prospectus supplement and the accompanying prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement and the accompanying prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

When used herein, unless the context requires otherwise, references to the “Company,” “we,” “our” and “us” refer to Soluna Holdings, Inc., a Nevada corporation.

All trademarks or trade names referred to in this prospectus supplement and the accompanying prospectus are the property of their respective owners. Solely for convenience, the trademarks and trade names in this prospectus supplement and the accompanying prospectus are referred to without the ^® and ™ symbols, but such references should not be construed as any indicator that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto. We do not intend the use or display of other companies’ trademarks and trade names to imply a relationship with, or endorsement or sponsorship of us by, any other companies.

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying prospectus and the documents incorporated by reference in this prospectus supplement contain, and our officers and representatives may from time to time make, forward-looking statements that involve substantial risks and uncertainties. In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “estimate,” “believe,” “estimate,” “predict,” “potential” or “continue” or the negative of these terms or other similar expressions intended to identify statements about the future. These statements speak only as of the date of this prospectus supplement and involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our business, financial condition and results of operations. These forward-looking statements include, without limitation, statements about the following:

The foregoing does not represent an exhaustive list of matters that may be covered by the forward-looking statements contained herein and in the documents incorporated by reference herein or risk factors that we are faced with that may cause our actual results to differ from those anticipate in our forward-looking statements. Factors that may affect our results include, but are not limited to, the risks and uncertainties discussed in the “Risk Factors” section on page 8 of this prospectus supplement, in our most recent Annual Report on Form 10-K or in other reports we file with the SEC.

Moreover, new risks regularly emerge, and it is not possible for our management to predict or articulate all risks we face, nor can we assess the impact of all risks on our business or the extent to which any risk, or combination of risks, may cause actual results to differ from those contained in any forward-looking statements. The Private Securities Litigation Reform Act of 1995 and Section 27A of the Securities Act do not protect any forward-looking statements that we make in connection with this offering. All forward-looking statements included in this prospectus supplement, the accompanying prospectus and in the documents incorporated by reference in this prospectus supplement or accompanying prospectus are based on information available to us on the date of this prospectus supplement, the accompanying prospectus or the date of the applicable document incorporated by reference. Except to the extent required by applicable laws or rules, we undertake no obligation to publicly update or revise any forward-looking statement, whether written or oral, that may be made from time to time, whether as a result of new information, future events or otherwise. All subsequent written and oral forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the cautionary statements contained above and throughout this prospectus supplement, the accompanying prospectus and in the documents incorporated by reference in this prospectus supplement. We qualify all of our forward-looking statements by these cautionary statements.

You should rely only on the information in this prospectus supplement. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely upon it.

PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights selected information about us, this offering and information appearing elsewhere in this prospectus supplement, in the accompanying prospectus and in the documents incorporated by reference herein and therein. This summary is not complete and does not contain all the information you should consider before investing in our securities pursuant to this prospectus supplement and the accompanying prospectus. Before making an investment decision, to fully understand this offering and its consequences to you, you should carefully read this entire prospectus supplement and the accompanying prospectus, including “Risk Factors,” the financial statements, and related notes, and the other information incorporated by reference herein and therein.

Overview

Our mission is to make renewable energy a global superpower using computing as a catalyst.

We develop and operate digital infrastructure that taps into a growing global opportunity: the convergence of renewable energy and High-Performance Computing (“HPC”). We call this model Renewable Computing™.

Across the world, vast amounts of clean energy go to waste due to curtailment. At the same time, there is a critical shortage of power for energy-intensive infrastructure like artificial intelligence (“AI”), HPC, and Bitcoin mining. Renewable Computing™ bridges this gap-unlocking stranded renewable energy and turning it into scalable computing power.

We build, own or co-own, and operate data centers co-located with wind, solar, and hydroelectric plants. Our modular and scalable design supports high-throughput, batchable applications such as AI, Bitcoin, and-soon-HPC workloads. These facilities are managed by MaestroOS™, our proprietary operating system (“MaestroOS”), which continuously analyzes signals like local power pricing, weather, grid demand, and market conditions to optimize performance and economics.

This intelligent orchestration enables long-term asset monetization and attractive returns on invested capital. Our approach is purpose-built for the energy transition. We specialize in curtailment solutions, working closely with leading renewable energy developers to access underutilized, low-cost power. Our behind-the-meter model allows us to draw energy directly from the plant or the grid, while also providing demand response services-reducing costs and enhancing grid resilience.

A key strategic advantage is our model of co-locating data centers directly with renewable power generation assets. By building behind the meter, we are able to bypass long interconnection queues and source electricity directly from the generation site. This structure not only improves power economics, but also accelerates time-to-market-an increasingly important factor for companies with large, time-sensitive computing workloads such as AI and HPC.

With a repeatable strategy and a growing pipeline of projects, we are scaling a new category of digital infrastructure-one that energizes the grid, lowers computing costs, and advances a more sustainable future.

We operate across multiple business lines and generate revenue from four primary sources, as described below:

Lines of Business

Bitcoin Mining Business

We engage in proprietary Bitcoin mining, a process that verifies transactions and secures the Bitcoin blockchain. This process involves the use of specialized computing equipment to solve complex cryptographic algorithms. Miners compete to solve these algorithms; the first to do so is awarded a predetermined number of newly issued Bitcoins (the “Block Reward”) and any transaction fees associated with that block.

We participate in one or more mining pools-collaborative networks of miners who combine computing power to improve the probability of earning rewards. Block Rewards earned by the pool are distributed among participants based on each member’s proportional contribution. This model helps reduce revenue volatility compared to solo mining operations.

Our mining operations are energy-intensive and require significant computational resources. We operate data centers equipped with both proprietary and third-party hardware and software. Our proprietary data center operating system, MaestroOS, is used to optimize performance, manage power consumption, and increase operational efficiency. Revenue from Bitcoin mining consists of Block Rewards and transaction fees and is recognized upon receipt in accordance with applicable accounting guidance. Upon receipt, all digital assets are promptly converted into U.S. dollars through the Coinbase cryptocurrency exchange.

The profitability of this business is affected by several variables, including the market price of Bitcoin, global network hash rate, mining difficulty, electricity and infrastructure costs, and mining pool fees. In addition, Bitcoin undergoes a periodic “halving” event approximately every four years, reducing the Block Reward and potentially impacting future revenue. For the year ended December 31, 2024, our Bitcoin Mining Business represented approximately 45% of total revenue.

Bitcoin Hosting Business

We provide colocation and hosting services for third-party Bitcoin mining customers at our data centers. Customers lease space based on their power requirements. Our current customer base includes several large-scale Bitcoin miners. Contracts typically range from 12 to 24 months in duration.

We offer two primary commercial structures:

In 2024, our Bitcoin Hosting Business accounted for approximately 50% of total revenue. Revenue in this business was concentrated among a small number of customers. One customer accounted for 56% of hosting revenue and 28% of total revenue in 2024. This customer terminated its agreement during the fourth quarter of 2024. As of March 2025, we replaced 100% of the lost hosting capacity with minimal operational disruption.

High Performance Computing (HPC) Business

In June 2024, we began providing Graphic Processing Units (“GPUs”)-as-a-Service in partnership with Hewlett Packard Enterprise Company (“HPE”), offering GPU resources to startups, enterprises, and GPU marketplaces for a fee. In March 2025, we terminated our agreement with HPE.

We are currently developing new infrastructure projects intended to support AI and HPC workloads. These efforts include engagement with potential joint venture partners, conducting site and feasibility studies, securing access to power and land, and performing other early-stage development activities.

Our first planned AI/HPC colocation project is Project Kati, which is in advanced development. Additional projects, including the announced Project Rosa, are also in progress. For the year ended December 31, 2024, we generated minimal revenue from our HPC Business.

Demand Response Business

We provide demand response services to grid operators and utilities by leveraging our data centers as dispatchable energy resources. In select states where we operate, our data centers are enrolled in ancillary services programs that support grid reliability.

Under these programs, we commit to reducing a facility’s power consumption to a predetermined level when called upon by the grid operator. In return, we receive compensation for maintaining this dispatch capability, provided we meet specific performance criteria. For example, to qualify for compensation in a given period-typically monthly-the data center must meet minimum uptime and availability requirements.

For the year ended December 31, 2024, our Demand Response Business represented approximately 6% of total revenue.

Implications of Being a Smaller Reporting Company

We qualify as a “smaller reporting company” under applicable SEC regulations. A smaller reporting company may take advantage of reduced reporting requirements that are otherwise applicable to public companies. These provisions include, but are not limited to:

We will continue to be a smaller reporting company as long as we have a public float (determined as of the end of our second fiscal quarter) of less than $250 million or have annual revenues of less than $100 million as of the last fiscal year for which we have audited financial statements and a public float of less than $700 million.

We have elected to take advantage of certain of the reduced disclosure obligations in the registration statement of which this prospectus is a part and may elect to take advantage of other reduced reporting requirements in future filings. As a result, the information that we provide to our stockholders may be different than you might receive from other public reporting companies in which you hold equity interests.

Corporate Information

Soluna Holdings, Inc. (“SHI”), formerly known as Mechanical Technology, Incorporated, which was originally incorporated in the State of New York in 1961, reincorporated in the State of Nevada on March 29, 2021, and is headquartered in Albany, New York. Effective November 2, 2021, the Company changed its name from “Mechanical Technology, Incorporated” (or “MTI”) to “Soluna Holdings, Inc.” On October 29, 2021, Soluna Callisto Holdings, Inc. merged into Soluna Computing, Inc. (“SCI”), a private green data center development company and a subsidiary of SHI. MTI Instruments, Inc., a subsidiary of SHI, was sold on April 11, 2022. On March 23, 2021, our common stock commenced trading on the Nasdaq Stock Market LLC (“Nasdaq”). We formed a wholly owned subsidiary of SHI on December 27, 2023, Soluna Digital, Inc. (“Soluna Digital,” or “SDI”). Effective December 31, 2023, SCI transferred substantially all of its assets to SHI or its subsidiaries, including SDI.

Our principal executive office is located at 325 Washington Avenue Extension, Albany, NY 12205, and our phone number is (516) 216-9257. Our principal website address is www.solunacomputing.com.

Information contained in, or accessible through, our website does not constitute part of this prospectus or registration statement and inclusions of our website address in this prospectus or registration statement are inactive textual references only. You should not rely on any such information in making your decision whether to purchase our securities.

We make available free of charge on or through our website access to press releases and investor presentations, as well as all materials that we file electronically with the SEC, including our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports, filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after electronically filing such materials with, or furnishing them to, the SEC. The SEC maintains an Internet website, www.sec.gov, that contains reports, proxy and information statements and other information that we file electronically with the SEC.

THE OFFERING

The number of our common stock to be outstanding after the offering is based on 13,567,176 of our common stock outstanding as of April 28, 2025 and excludes:

RISK FACTORS

Investing in our securities involves a high degree of risk. Before deciding whether to invest in our securities, you should carefully consider the risk factors we describe in this prospectus supplement and in any related free writing prospectus that we may authorize to be provided to you or in any report incorporated by reference into this prospectus supplement, including our Annual Report on Form 10-K for the year ended December 31, 2024, or any Quarterly Report on Form 10-Q that is incorporated by reference into this prospectus supplement. Although we discuss key risks in those risk factor descriptions, additional risks not currently known to us or that we currently deem immaterial also may impair our business. Our subsequent filings with the SEC may contain amended and updated discussions of significant risks. We cannot predict future risks or estimate the extent to which they may affect our financial performance.

Risks Relating to this Offering

We may allocate the net proceeds from this offering in ways that you or other stockholders may not approve.

We currently intend to use the net proceeds of this offering, if any, for working capital, project-level equity, and general corporate purposes, which may include capital expenditures and business expansions. This expected use of the net proceeds from this offering represents our intentions based upon our current plans and business conditions. The amounts and timing of our actual expenditures may vary significantly depending on numerous factors, including the progress of our development efforts, and any unforeseen cash needs. Because the number and variability of factors that will determine our use of the proceeds from this offering, their ultimate use may vary substantially from their currently intended use. As a result, our management will retain broad discretion over the allocation of the net proceeds from this offering and could spend the proceeds in ways that do not necessarily improve our operating results or enhance the value of our common stock. See “Use of Proceeds.”

It is not possible to predict the aggregate proceeds resulting from sales made under the Sales Agreement.

Subject to certain limitations in the Sales Agreement and compliance with applicable law, we have the discretion to deliver a placement notice to the Sales Agent at any time throughout the term of the Sales Agreement. The number of shares that are sold through the Sales Agent after delivering a placement notice will fluctuate based on a number of factors, including the market price of our common stock during the sales period, the limits we set with Wainwright in any applicable placement notice, and the demand for shares of our common stock during the sales period. Because the price per share of each share sold will fluctuate during the sales period, it is not currently possible to predict the aggregate proceeds to be raised in connection with those sales.

You may experience immediate and substantial dilution in the book value per share of the common stock you purchase.

The shares sold in this offering, if any, will be sold from time to time at various prices. Because the prices per share at which shares of our common stock are sold in this offering could be substantially higher than the book value per share of our common stock, you may suffer immediate and substantial dilution in the net tangible book value of the common stock you purchase in this offering.

The shares of common stock offered hereby will be sold in “at the market offerings,” and investors who buy shares at different times will likely pay different prices.

Investors who purchase shares in this offering at different times will likely pay different prices, and so may experience different levels of dilution and different outcomes in their investment results. We will have discretion, subject to market demand, to vary the timing, prices, and number of shares sold in this offering. In addition, subject to the final determination by our board of directors, there is no minimum or maximum sales price for shares to be sold in this offering. Investors may experience a decline in the value of the shares they purchase in this offering as a result of sales made at prices lower than the prices they paid.

The actual number of shares we will issue under the Sales Agreement at any one time or in total, is uncertain.

Subject to certain limitations in the Sales Agreement and compliance with applicable law, we have the discretion to deliver placement notices to Wainwright at any time throughout the term of the Sales Agreement. The number of shares that are sold by Wainwright as our Sales Agent after we deliver a placement notice will fluctuate based on the market price of the common stock and the trading volume of our common stock during the sales period and limits we set with Wainwright.

You may experience future dilution as a result of future equity offerings.

In order to raise additional capital, we may in the future offer additional shares of common stock or other securities convertible into or exchangeable for our common stock at prices that may not be the same as the price per share in this offering. We may sell shares or other securities in another offering at a price per share that is less than the price per share paid by the investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. The price per share at which we sell additional shares of common stock, or securities convertible or exchangeable into shares of common stock, in future transactions may be higher or lower than the price per share paid by investors in this offering. If any of the above should occur, our stockholders, including investors who purchase shares of common stock in this offering, will experience additional dilution, and any such issuances may result in downward pressure on the price of our common stock.

We do not currently intend to pay dividends or other distributions on our common stock in the foreseeable future, and consequently, any gains from an investment in our common stock will likely depend on appreciation in the price of our common stock.

We have never declared or paid cash dividends on our common stock and do not anticipate paying any cash dividends or other distributions to holders of our common stock in the foreseeable future. Consequently, investors must rely on sales of their common stock after price appreciation, which may never occur, as the only way to realize any future gains on their investments. There is no guarantee that our common stock will appreciate in value or even maintain the price at which the stockholders have purchased their shares.

USE OF PROCEEDS

We currently intend to use the net proceeds from this offering, if any, for working capital, project-level equity, and general corporate purposes. Pursuant to Amendment No. 1 to Securities Purchase Agreement, dated October 3, 2024, between the Company and the holder of our Series B Preferred Stock, we are required to pay a consent fee equaling 10% of the gross proceeds from this offering to the holder of our Series B Preferred Stock.

The timing and amount of our actual expenditures will be based on many factors, including cash flows from operations and the anticipated growth of our business. As of the date of this prospectus supplement, we cannot specify with certainty all of the particular uses for the net proceeds to us from this offering. As a result, our management will have broad discretion regarding the timing and application of the net proceeds from this offering. Pending their ultimate use, we intend to invest the net proceeds in short-term, investment-grade, interest-bearing instruments.

DIVIDEND POLICY

We have never declared or paid cash dividends on our capital stock. We currently intend to retain our future earnings, if any, for use in our business and therefore do not anticipate paying cash dividends or other distributions in the foreseeable future. Payment of future dividends or other distributions, if any, will be at the discretion of our board of directors, subject to applicable law, after taking into account various factors, including our financial condition, operating results, current and anticipated cash needs and plans for expansion.

PLAN OF DISTRIBUTION

We entered into the Sales Agreement with Wainwright, pursuant to which we may issue and sell from time to time shares of our common stock having an aggregate offering price of up to the amount set forth on the cover page of this prospectus, as supplemented from time to time, through or to Wainwright acting as sales agent or principal. Sales of the common stock, if any, will be made by any method permitted by law deemed to be an “at-the-market offering” as defined in Rule 415(a)(4) promulgated under the Securities Act, including sales made directly on or through Nasdaq Capital Market, the existing trading market for our common stock, or any other existing trading market in the United States for our common stock, sales made to or through a market maker other than on an exchange or otherwise, directly to Wainwright as principal, in negotiated transactions at market prices prevailing at the time of sale or at prices related to such prevailing market prices if authorized by us in writing, and/or in any other method permitted by law.

Wainwright will offer our common stock at prevailing market prices subject to the terms and conditions of the Sales Agreement. We will designate the number of shares we desire to sell, the time period during which sales are requested to be made, any limitation on the number of shares that may be sold in one day and any minimum price below which sales may not be made. Subject to the terms and conditions of the sales agreement, Wainwright will use its commercially reasonable efforts consistent with its normal trading and sales practices and applicable law and regulations to sell on our behalf all of the shares of common stock requested to be sold by us. We or Wainwright may suspend the offering of the common stock being made through Wainwright under the Sales Agreement upon proper notice to the other party and pursuant to the terms of the Sales Agreement.

Settlement for sales of common stock will occur on the first trading day following the date on which any sales are made (or such shorter settlement cycle as may be in effect under the Exchange Act from time to time), or on some other date that is agreed upon by us and Wainwright in connection with a particular transaction, in return for payment of the net proceeds to us. Sales of our common stock as contemplated in this prospectus will be settled through the facilities of The Depository Trust Company or by such other means as we and Wainwright may agree upon. There is no arrangement for funds to be received in an escrow, trust or similar arrangement.

We will pay Wainwright a cash commission equal to 3.0% of the gross sales price per share of common stock sold by Wainwright under the Sales Agreement. Because there is no minimum offering amount required as a condition to this offering, the actual total offering amount, sales commissions and net proceeds to us, if any, are not determinable at this time. Pursuant to the terms of the Sales Agreement, we have agreed to pay Wainwright a fee not to exceed $50,000 for the reasonable fees and expenses of its legal counsel (excluding any periodic due diligence fees) incurred in connection with entering into the transactions contemplated by the Sales Agreement. Additionally, pursuant to the terms of the Sales Agreement, we have also agreed to reimburse Wainwright $3,500 per due diligence update session conducted in connection with each such date we file our Annual Report on Form 10-K or Quarterly Reports on Form 10-Q or an additional prospectus supplement for this offering. We estimate that the total expenses of the offering payable by us, excluding commissions payable to Wainwright under the Sales Agreement, will be approximately $200,000, assuming we sell the entire amount offered pursuant to this prospectus supplement and the accompanying prospectus. We will disclose in our Annual Reports on Form 10-K and Quarterly Reports on Form 10-Q, as applicable, the number of shares of our common stock sold through Wainwright under the Sales Agreement, the net proceeds to us and the compensation paid by us with respect to sales under the Sales Agreement during the relevant quarter.

In connection with the sales of common stock on our behalf, Wainwright will be deemed to be an “underwriter” within the meaning of the Securities Act, and the compensation paid to Wainwright will be deemed to be underwriting commissions or discounts. We have agreed in the Sales Agreement to provide indemnification and contribution to Wainwright against certain liabilities, including liabilities under the Securities Act.

The offering of our shares of common stock pursuant to the Sales Agreement will terminate upon termination of the Sales Agreement or as otherwise permitted therein. We or Wainwright may terminate the Sales Agreement at any time, pursuant to the terms of the Sales Agreement.

To the extent required by Regulation M, Wainwright will not engage in any market making activities involving our shares of common stock while the offering is ongoing under this prospectus supplement.

From time to time, Wainwright and its affiliates have and may provide in the future various advisory, investment and commercial banking and other services to us and our affiliates in the ordinary course of business, for which they have received and may continue to receive customary fees and commissions. In addition, in the ordinary course of its various business activities, Wainwright and its affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (which may include bank loans) for their own account and for the accounts of their customers. Such investments and securities activities may involve securities and/or instruments of ours or our affiliates. Wainwright or its affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or financial instruments and may hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

This summary of the material provisions of the Sales Agreement does not purport to be a complete statement of its terms and conditions. A copy of the Sales Agreement will be filed with the SEC on a Current Report on Form 8-K.

This prospectus supplement and accompanying prospectus in electronic format may be made available on a website maintained by Wainwright and Wainwright may distribute this prospectus electronically.

Our transfer agent and registrar for our common stock is The transfer agent and registrar for our common stock is Equiniti Trust Company, LLC.

LEGAL MATTERS

The validity of the shares of common stock offered by this prospectus supplement will be passed upon by Brownstein Hyatt Farber Schreck, LLP, Las Vegas, Nevada. Wainwright is being represented in connection with this offering by Ellenoff Grossman & Schole LLP, New York, New York.

EXPERTS

The consolidated balance sheets of Soluna Holdings, Inc. and its subsidiaries as of December 31, 2024 and 2023, and the related consolidated statements of operations, changes in equity, and cash flows for each of the years then ended have been audited by UHY LLP, independent registered public accounting firm, as stated in their report which is incorporated herein by reference. Such financial statements have been incorporated herein by reference in reliance on the report of such firm given upon their authority as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

This prospectus constitutes a part of a registration statement on Form S-3 filed under the Securities Act. As permitted by the SEC’s rules, this prospectus and any prospectus supplement, which form a part of the registration statement, do not contain all the information that is included in the registration statement. You will find additional information about us in the registration statement. Any statements made in this prospectus or any prospectus supplement concerning legal documents are not necessarily complete and you should read the documents that are filed as exhibits to the registration statement or otherwise filed with the SEC for a more complete understanding of the document or matter.

We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read, without charge, and copy the documents we file at the SEC’s public reference rooms in Washington, D.C. at 100 F Street, NE, Room 1580, Washington, DC 20549. You can request copies of these documents by writing to the SEC and paying a fee for the copying cost. Please call the SEC at 1-800-SEC-0330 for further information on the public reference rooms. Our SEC filings are also available to the public at no cost from the SEC’s website at http://www.sec.gov.

INCORPORATION OF DOCUMENTS BY REFERENCE

We have filed a registration statement on Form S-3 with the SEC under the Securities Act. This prospectus supplement and the accompanying prospectus is part of the registration statement but the registration statement includes and incorporates by reference additional information and exhibits. The SEC permits us to “incorporate by reference” the information contained in documents we file with the SEC, which means that we can disclose important information to you by referring you to those documents rather than by including them in this prospectus supplement and the accompanying prospectus. Information that is incorporated by reference is considered to be part of this prospectus supplement and the accompanying prospectus and you should read it with the same care that you read this prospectus supplement. Information that we file later with the SEC will automatically update and supersede the information that is either contained, or incorporated by reference, in this prospectus supplement and the accompanying prospectus, and will be considered to be a part of this prospectus supplement and the accompanying prospectus from the date those documents are filed.

We have filed with the SEC, and incorporate by reference in this prospectus supplement:

We also incorporate by reference all additional documents that we file with the SEC under the terms of Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act that are made after the initial filing date of the registration statement of which this prospectus supplement is a part until the offering of the particular securities covered by a prospectus supplement or term sheet has been completed. We are not, however, incorporating, in each case, any documents or information that we are deemed to furnish and not file in accordance with SEC rules.

You may request, and we will provide you with, a copy of these filings, at no cost, by contacting us at:

Soluna Holdings, Inc.

325 Washington Avenue Extension

Albany, NY 12205

(518) 218-2550

Attn: Christopher Gandolfo

[email protected]

PROSPECTUS

Soluna Holdings, Inc.

$100,000,000

Common Stock

Preferred Stock

Warrants

Debt Securities

Subscription Rights

Units

We may offer, issue and sell from time to time together or separately, in one or more offerings, any combination of (i) our common stock, par value $0.001 per share (“common stock”), (ii) our preferred stock, which we may issue in one or more series, (iii) warrants, (iv) senior or subordinated debt securities, (v) subscription rights and (vi) units. The debt securities may consist of debentures, notes, or other types of debt. The debt securities, preferred stock, warrants and subscription rights may be convertible into, or exercisable or exchangeable for, common or preferred stock or other securities of ours. The units may consist of any combination of the securities listed above.

The aggregate public offering price of the securities that we are offering will not exceed $100,000,000. We will offer the securities in an amount and on terms that market conditions will determine at the time of the offering. Our common stock and our 9.0% Series A Cumulative Perpetual Preferred Stock, par value $0.001 per share (the “Series A Preferred Stock”), are listed on the Nasdaq Capital Market under the symbols “SLNH” and “SLNHP”, respectively. The last reported sale price for our common stock and our Series A Preferred Stock on April 17, 2025 on the Nasdaq Capital Market was $0.62 and $4.60, respectively. You are urged to obtain current market quotations of our common stock and Series A Preferred Stock. As of the date of this prospectus, we have no warrants, debt securities, subscription rights or units listed or quoted on any securities exchange or other nationally recognized trading market. Each prospectus supplement will indicate if the securities offered thereby will be listed or quoted on any securities exchange or another nationally recognized trading market.

As of the date of this prospectus, the aggregate market value of our outstanding common stock held by non-affiliates, or the public float, was $14,027,685, which was calculated based on 9,542,643 shares of our outstanding common stock held by non-affiliates at a price of $1.47 per share, the closing price of our common stock on February 19, 2025. Pursuant to General Instruction I.B.6 of Form S-3, in no event will we sell securities pursuant to this prospectus with a value of more than one-third of the aggregate market value of our common stock held by non-affiliates in any 12-month period, so long as the aggregate market value of our common stock held by non-affiliates is less than $75,000,000. During the 12 calendar months prior to, and including, the date of this prospectus, we have not sold any securities pursuant to General Instruction I.B.6 of Form S-3.

Investing in our securities involves risk. You should carefully consider the risks that we refer you to under the section captioned “Risk Factors” in this prospectus on page 8 and in other filings we make with the Securities and Exchange Commission before buying our securities.

Should we offer any of the securities described in this prospectus, we will provide you with the specific terms of the particular securities being offered in a supplement to this prospectus. You should read this prospectus and any supplement, together with additional information described under the headings “Additional Information” and “Incorporation of Certain Information by Reference” carefully before you invest. This prospectus may not be used to sell securities unless accompanied by a prospectus supplement.

We may sell these securities directly to our stockholders or to other purchasers or through agents on our behalf or through underwriters or dealers as designated from time to time. If any agents or underwriters are involved in the sale of any of these securities, the applicable prospectus supplement will provide the names of the agents or underwriters and any applicable fees, commissions or discounts.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is April 29, 2025.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission (the “SEC”) using a “shelf” registration process. Under this shelf registration process, we may from time to time offer and sell, in one or more offerings, any or all of the securities described in this prospectus, separately or together, up to an aggregate offering price of $100,000,000. This prospectus provides you with a general description of the securities we may offer. When we issue securities pursuant to this prospectus, we will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and any prospectus supplement together with additional information described under the heading “Additional Information” and “Incorporation of Certain Information by Reference.”

You may only rely on the information contained in this prospectus and the accompanying prospectus supplement or in any free writing prospectus prepared by or on behalf of us or to which we have referred you. We have not authorized anyone to provide you with different information. This prospectus and any prospectus supplement do not constitute an offer to sell or a solicitation of an offer to buy any securities other than the securities offered by this prospectus and the prospectus supplement. This prospectus and any prospectus supplement do not constitute an offer to sell or a solicitation of an offer to buy any securities in any circumstances in which such offer or solicitation is unlawful. Neither the delivery of this prospectus or any prospectus supplement nor any sale made hereunder shall, under any circumstances, create any implication that there has been no change in our affairs since the date of this prospectus or such prospectus supplement or that the information contained by reference to this prospectus or any prospectus supplement is correct as of any time after its date.

Unless otherwise stated or the context otherwise indicates, references to “Soluna,” the “Company,” “we,” “our,” “us,” or similar terms refer to Soluna Holdings, Inc. and its subsidiaries.

PROSPECTUS SUMMARY

The following summary highlights some information from this prospectus. It is not complete and does not contain all of the information that you should consider before making an investment decision. You should read this entire prospectus, including the “Risk Factors” section on page 8 and the disclosures to which that section refers you, the financial statements and related notes and the other more detailed information appearing elsewhere or incorporated by reference into this prospectus before investing in any of the securities described in this prospectus.

Overview

Our mission is to make renewable energy a global superpower using computing as a catalyst.

We develop and operate digital infrastructure that taps into a growing global opportunity: the convergence of renewable energy and High-Performance Computing (“HPC”). We call this model Renewable Computing™.

Across the world, vast amounts of clean energy go to waste due to curtailment. At the same time, there is a critical shortage of power for energy-intensive infrastructure like artificial intelligence (“AI”), HPC, and Bitcoin mining. Renewable Computing™ bridges this gap-unlocking stranded renewable energy and turning it into scalable computing power.

We build, own or co-own, and operate data centers co-located with wind, solar, and hydroelectric plants. Our modular and scalable design supports high-throughput, batchable applications such as AI, Bitcoin, and-soon-HPC workloads. These facilities are managed by MaestroOS™, our proprietary operating system (“MaestroOS”), which continuously analyzes signals like local power pricing, weather, grid demand, and market conditions to optimize performance and economics.

This intelligent orchestration enables long-term asset monetization and attractive returns on invested capital. Our approach is purpose-built for the energy transition. We specialize in curtailment solutions, working closely with leading renewable energy developers to access underutilized, low-cost power. Our behind-the-meter model allows us to draw energy directly from the plant or the grid, while also providing demand response services-reducing costs and enhancing grid resilience.

A key strategic advantage is our model of co-locating data centers directly with renewable power generation assets. By building behind the meter, we are able to bypass long interconnection queues and source electricity directly from the generation site. This structure not only improves power economics, but also accelerates time-to-market-an increasingly important factor for companies with large, time-sensitive computing workloads such as AI and HPC.

With a repeatable strategy and a growing pipeline of projects, we are scaling a new category of digital infrastructure-one that energizes the grid, lowers computing costs, and advances a more sustainable future.

We operate across multiple business lines and generate revenue from four primary sources, as described below:

Lines of Business

Bitcoin Mining Business

We engage in proprietary Bitcoin mining, a process that verifies transactions and secures the Bitcoin blockchain. This process involves the use of specialized computing equipment to solve complex cryptographic algorithms. Miners compete to solve these algorithms; the first to do so is awarded a predetermined number of newly issued Bitcoins (the “Block Reward”) and any transaction fees associated with that block.

We participate in one or more mining pools-collaborative networks of miners who combine computing power to improve the probability of earning rewards. Block Rewards earned by the pool are distributed among participants based on each member’s proportional contribution. This model helps reduce revenue volatility compared to solo mining operations.

Our mining operations are energy-intensive and require significant computational resources. We operate data centers equipped with both proprietary and third-party hardware and software. Our proprietary data center operating system, MaestroOS, is used to optimize performance, manage power consumption, and increase operational efficiency. Revenue from Bitcoin mining consists of Block Rewards and transaction fees and is recognized upon receipt in accordance with applicable accounting guidance. Upon receipt, all digital assets are promptly converted into U.S. dollars through the Coinbase cryptocurrency exchange.

The profitability of this business is affected by several variables, including the market price of Bitcoin, global network hash rate, mining difficulty, electricity and infrastructure costs, and mining pool fees. In addition, Bitcoin undergoes a periodic “halving” event approximately every four years, reducing the Block Reward and potentially impacting future revenue. For the year ended December 31, 2024, our Bitcoin Mining Business represented approximately 45% of total revenue.

Bitcoin Hosting Business

We provide colocation and hosting services for third-party Bitcoin mining customers at our data centers. Customers lease space based on their power requirements. Our current customer base includes several large-scale Bitcoin miners. Contracts typically range from 12 to 24 months in duration.

We offer two primary commercial structures:

In 2024, our Bitcoin Hosting Business accounted for approximately 50% of total revenue. Revenue in this business was concentrated among a small number of customers. One customer accounted for 56% of hosting revenue and 28% of total revenue in 2024. This customer terminated its agreement during the fourth quarter of 2024. As of March 2025, we replaced 100% of the lost hosting capacity with minimal operational disruption.

High Performance Computing (HPC) Business

In June 2024, we began providing Graphic Processing Units (“GPUs”)-as-a-Service in partnership with Hewlett Packard Enterprise Company (“HPE”), offering GPU resources to startups, enterprises, and GPU marketplaces for a fee. In March 2025, we terminated our agreement with HPE.

We are currently developing new infrastructure projects intended to support AI and HPC workloads. These efforts include engagement with potential joint venture partners, conducting site and feasibility studies, securing access to power and land, and performing other early-stage development activities.

Our first planned AI/HPC colocation project is Project Kati, which is in advanced development. Additional projects, including the announced Project Rosa, are also in progress. For the year ended December 31, 2024, we generated minimal revenue from our HPC Business.

Demand Response Business

We provide demand response services to grid operators and utilities by leveraging our data centers as dispatchable energy resources. In select states where we operate, our data centers are enrolled in ancillary services programs that support grid reliability.

Under these programs, we commit to reducing a facility’s power consumption to a predetermined level when called upon by the grid operator. In return, we receive compensation for maintaining this dispatch capability, provided we meet specific performance criteria. For example, to qualify for compensation in a given period-typically monthly-the data center must meet minimum uptime and availability requirements.

For the year ended December 31, 2024, our Demand Response Business represented approximately 6% of total revenue.

Recent Developments

Soluna Cloud - Termination of HPE Agreement

Soluna launched Project Ada- its GPU-as-a-Service business, via Soluna Cloud, Inc. (“Soluna Cloud”), a subsidiary of the Company, earlier in 2024, in order to achieve two primary goals:

As a point of entry into Project Ada, Soluna AL CloudCo, LLC (“CloudCo”), a subsidiary of Soluna Cloud, entered into the HPC & AI Cloud Services Agreement and HPE Greenlake Services Custom Statement of Work with HPE on June 18, 2024, that provided data center and cloud services for AI and supercomputing applications, utilizing NVIDIA H100 GPUs (together with the associated Statement of Work, the “HPE Agreement”).

At the time of launch, the market for NVIDIA H100 GPUs was characterized by constrained supply and strong pricing, which aligned with the economics of the fixed-cost HPE Agreement. However, by the end of 2024, the GPU market shifted significantly. Lead times for NVIDIA H100 GPUs shortened from over 50 weeks in 2023 to 8-12 weeks by the end of 2024, easing supply constraints and reducing urgency among buyers. At the same time, market demand shifted toward larger GPU clusters than those available under the HPE Agreement, making it difficult to secure long-term, reserved contracts at profitable rates. The expected release of NVIDIA’s H200 Blackwell architecture also caused some customers to delay purchases. Although release timelines were impacted by design issues, the prospect of next-generation technology contributed to hesitancy in NVIDIA H100 GPU acquisition. Competitive pressure from alternative GPU vendors further softened demand and market pricing. As a result, Soluna Cloud’s business progressed more slowly than anticipated. Revenues were first recognized in December 2024, with modest growth in early 2025. During the last six months, our engagement with potential financing and operating partners for AI/HPC confirmed that rather than continuing the effort to lease and resell GPU/HPC chips, refocusing on our core strength - creating, developing, financing and operating our extensive pipeline of potential bitcoin and AI hosting facilities - will create far more value for us and our shareholders.

In light of these developments, on March 24, 2025, CloudCo sent notice of its termination of the HPE Agreement for convenience. Subsequently, on March 26, 2025, HPE sent notice of its termination of the HPE Agreement for cause, effective immediately, due to CloudCo’s material breach of its payment obligations that remained uncured for more than thirty (30) days. In accordance with the terms of the HPE Agreement, upon a termination for cause by HPE, CloudCo must pay HPE the remaining payment stream under the term of the HPE Agreement of approximately $19.3 million as of March 31, 2025, including all upfront payments and monthly charges, plus any fees incurred for the terminated Services (as defined in the HPE Agreement).

SEPA

On August 12, 2024, we entered into a Standby Equity Purchase Agreement (the “SEPA”) with YA II PN, LTD., a Cayman Islands exempt limited company (“YA”). Pursuant to the terms of the SEPA, we agreed to issue and sell to YA, from time to time, and YA agreed to purchase from us, up to $25 million of shares of our common stock (the “SEPA Shares”). We and YA also entered into a registration rights agreement (the “Registration Rights Agreement”), pursuant to which we agreed to prepare and file with the SEC a Registration Statement on Form S-1, registering the resale of the SEPA Shares. On November 12, 2024, we filed a registration statement on Form S-1 (File No. 333-282559) with the SEC for the resale by YA of 3,000,000 SEPA Shares, which was declared effective by the SEC on February 5, 2025. As of the date of this prospectus, we have issued and sold approximately 1.5 million shares of our common stock to YA pursuant to the SEPA for aggregate net proceeds to us of approximately $2.0 million. We intend to continue issuing shares of our common stock to YA pursuant to the SEPA in future periods.

Assignment and Assumption Agreements

CloudCo, Soluna Cloud, and the Company, entered into assignment and assumption agreements on October 1, 2024, with one of the accredited investors issued convertible notes and Class A, Class B and Class C common stock purchase warrants on October 25, 2021 (the “ Purchasers”), and two other parties introduced by that Purchaser, with respect to an aggregate of $1.25 million of notes (“Additional Notes”) issued by CloudCo (the “Assignment Agreements”). Pursuant to the Assignment Agreements, we will be able to purchase such notes for a purchase price of $750 thousand, or 60% of face value. The assignment and assumption will be effective once all conditions of the agreement are met including fulfilling the purchase price. As of December 31, 2024, the assignment and assumption of the Additional Notes has not been become effective, however on March 14, 2025, the Company has fulfilled the agreement and assumed the assignment and assumption of the Additional Notes for the remaining outstanding balance.

Galaxy Note

On March 12, 2025, Soluna SW LLC (the “SW Borrower”), a Delaware limited liability company and a subsidiary of Soluna SW Holdings LLC (“SW Holdings”), a Delaware limited liability company and a subsidiary of Soluna Digital, Inc. (“SDI”), a Nevada corporation and a subsidiary of the Company, entered into a Loan Agreement (the “Galaxy Loan Agreement”) with SW Holdings and Galaxy Digital LLC (the “Lender”). The Galaxy Loan Agreement comprises a term loan facility in the principal amount of $5.0 million (the “Term Loan Facility”). The Term Loan Facility bears interest at 15.0% per annum, unless an Event of Default (as defined therein) has occurred and is continuing, in which case the Galaxy Term Loan Facility shall bear interest at a rate of 5% above the then applicable interest rate. The Term Loan Facility will mature on March 12, 2030 and will be paid over a five-year term.

June SPA Modification

On June 20, 2024, pursuant to the terms and subject to the conditions of a Note Purchase Agreement (the “June SPA”) by and among (i) CloudCo, (ii) Soluna Cloud, (iii) the Company and (iv) the accredited investor named therein (the “Investor” and collectively, the “Note Parties), CloudCo issued to the Investor a secured promissory note in a principal amount equal to $12.5 million (the “Note”).

On March 23, 2025, the Note Parties entered into a Modification Agreement (the “Modification Agreement”) to, among other things, (i) provide for the deposit of 1,000,000 shares (the “Escrow Shares”) of our common stock into an escrow account maintained by Northland Securities, Inc., pursuant to an escrow agreement (as further described below), (ii) provide for the issuance to the Investor of a warrant to purchase shares of our common stock upon the release by the Investor of its lien on our property, (iii) amend the payment schedule of the Note to provide (a) for each of the six scheduled payments occurring after the earlier of the effectiveness of a registration statement for the resale of the Registrable Securities (as defined below) or the date that the Registrable Securities may be sold pursuant to Rule 144 under the Securities Act of 1933, as amended (the “Securities Act”), without any information requirements, the amount of principal and interest payable on such date shall be reduced by 50% (the aggregate amount of the six months of such reductions, the “Specified Amount”) and (b) if the aggregate amount of payments on the Note applied from the proceeds of the sale of the Escrow Shares on or prior to the last six scheduled payments is less than the Specified Amount (such difference, the “Make Whole Amount”), than the amount of each of the remaining scheduled payments shall be increased by an amount equal to the Make Whole Amount divided by the number of remaining scheduled payments, (iv) modify the Note such that the Note is now convertible into up to 2,500,000 shares (the “Conversion Shares”) of our common stock based on a conversion price of $5.00, (v) amend the Note to provide that we will be a direct co-obligor with CloudCo under the Note, and (vi) amend the SPA to allow us to organize or incorporate any subsidiary, over which we shall have voting or beneficial control, which is being formed with the intent to engage in a business or line of business substantially similar to that of Soluna Cloud or the Company, without first paying all of the principal and interest due under the Note and without first obtaining Investor’s prior written consent.

The net proceeds from dispositions of the Escrow Shares (i) at a price of up to $4.00 per share shall be applied to reduce the outstanding principal balance of the Note and (ii) at a price greater than $4.00 per share shall be applied first to reduce the outstanding principal balance of the Note in an amount equal to $4.00 per share of our common stock and then to the Investor. The outstanding share numbers in this prospectus do not give effect to the 1,000,000 Escrow Shares to be deposited by the Company in escrow.

Also under the Modification Agreement, we agreed to register for resale the Escrow Shares and Conversion Shares (together, the “Registrable Securities”) as promptly as commercially practicable, as determined by us, following the registration for resale of certain other securities. We also agreed to register for resale the shares of our common stock issuable upon exercise of the Warrant as promptly as commercially practicable, as determined by us, after the issuance of the Warrant.

Project Specific Developments

Project Dorothy 2

We are constructing Project Dorothy 2 which is a 48MW expansion of our flagship Project Dorothy that will be dedicated to Bitcoin Hosting. The site is expected to energize soon in the second quarter of 2025. This will enable the commencement of the commissioning of the first of 3 phases, each of 16MW, that will occur between May and October 2025 when the site is expected to be fully operational. As each phase is commissioned, it will begin to generate revenue, both due to Bitcoin Hosting and Demand Response Services.

Project Rosa

We are developing Project Rosa which is expected to be a 187MW data center for AI and Bitcoin hosting and other computing-intensive applications, as well as joint venture potential. It will be co-located with a wind farm in Texas. We have signed term sheets for both power and land purchase agreements in connection with this project.

Project Kati

We are developing Project Kati which is expected to be a 166MW data center for AI, machine learning, Bitcoin hosting and other computing-intensive applications, as well as joint venture potential. It will be co-located with a wind farm in Texas. We have received final ERCOT approval for the Reactive Power Study which is the last study required to exit planning. It is also waiting for required amendments to Las Majadas Wind Farm’s agreement with the transmission service provider to be completed.

Project Grace

We continue to develop a 2MW AI/HPC data center to be co-located with the same windfarm as Project Dorothy that will be the first construction of Soluna’s proprietary Helix design that remains in the concept design phase.

Project Hedy

We have signed a term sheet for power for Project Hedy, a new 120 MW data center co-located with a 200 MW wind farm in South Texas. The wind farm is owned by a new power partner–a multinational conglomerate that focuses on developing and managing sustainable infrastructure solutions, with a strong emphasis on renewable energy, water management, and services, aiming to contribute to a low-carbon economy and a better planet.

Implications of Being a Smaller Reporting Company

We qualify as a “smaller reporting company” under applicable SEC regulations. A smaller reporting company may take advantage of reduced reporting requirements that are otherwise applicable to public companies. These provisions include, but are not limited to:

We will continue to be a smaller reporting company as long as we have a public float (determined as of the end of our second fiscal quarter) of less than $250 million or have annual revenues of less than $100 million as of the last fiscal year for which we have audited financial statements and a public float of less than $700 million.

We have elected to take advantage of certain of the reduced disclosure obligations in the registration statement of which this prospectus is a part and may elect to take advantage of other reduced reporting requirements in future filings. As a result, the information that we provide to our stockholders may be different than you might receive from other public reporting companies in which you hold equity interests.

Corporate Information

Soluna Holdings, Inc. (“SHI”), formerly known as Mechanical Technology, Incorporated, which was originally incorporated in the State of New York in 1961, reincorporated in the State of Nevada on March 29, 2021, and is headquartered in Albany, New York. Effective November 2, 2021, the Company changed its name from “Mechanical Technology, Incorporated” (or “MTI”) to “Soluna Holdings, Inc.” On October 29, 2021, Soluna Callisto Holdings, Inc. merged into Soluna Computing, Inc. (“SCI”), a private green data center development company and a subsidiary of SHI. MTI Instruments, Inc., a subsidiary of SHI, was sold on April 11, 2022. On March 23, 2021, our common stock commenced trading on the Nasdaq Stock Market LLC (“Nasdaq”). We formed a wholly owned subsidiary of SHI on December 27, 2023, Soluna Digital, Inc. (“Soluna Digital,” or “SDI”). Effective December 31, 2023, SCI transferred substantially all of its assets to SHI or its subsidiaries, including SDI.

Our principal executive office is located at 325 Washington Avenue Extension, Albany, NY 12205, and our phone number is (516) 216-9257. Our principal website address is www.solunacomputing.com.

Information contained in, or accessible through, our website does not constitute part of this prospectus or registration statement and inclusions of our website address in this prospectus or registration statement are inactive textual references only. You should not rely on any such information in making your decision whether to purchase our securities.

We make available free of charge on or through our website access to press releases and investor presentations, as well as all materials that we file electronically with the SEC, including our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports, filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act of 1934 (the “Exchange Act”) as soon as reasonably practicable after electronically filing such materials with, or furnishing them to, the SEC. The SEC maintains an Internet website, www.sec.gov, that contains reports, proxy and information statements and other information that we file electronically with the SEC.

RISK FACTORS

Before purchasing any of the securities you should carefully consider the risk factors incorporated by reference in this prospectus from our most recent Annual Report on Form 10-K and any subsequent updates described in our Quarterly Reports on Form 10-Q and Current Reports on Form 8-K. For a description of these reports and information about where you can find them, see “Additional Information” and “Incorporation of Certain Information By Reference.” Additional risks not presently known or that we presently consider to be immaterial could subsequently materially and adversely affect our financial condition, results of operations, business and prospects.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents incorporated by reference in this prospectus contain, and our officers and representatives may from time to time make, forward-looking statements that involve substantial risks and uncertainties. In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “estimate,” “believe,” “estimate,” “predict,” “potential” or “continue” or the negative of these terms or other similar expressions intended to identify statements about the future. These statements speak only as of the date of this prospectus and involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our business, financial condition and results of operations. These forward-looking statements include, without limitation, statements about the following:

The foregoing does not represent an exhaustive list of matters that may be covered by the forward-looking statements contained herein and in the documents incorporated by reference herein or risk factors that we are faced with that may cause our actual results to differ from those anticipate in our forward-looking statements. Factors that may affect our results include, but are not limited to, the risks and uncertainties discussed in the “Risk Factors” section on page 8 of this prospectus, in our most recent Annual Report on Form 10-K or in other reports we file with the SEC.

Moreover, new risks regularly emerge, and it is not possible for our management to predict or articulate all risks we face, nor can we assess the impact of all risks on our business or the extent to which any risk, or combination of risks, may cause actual results to differ from those contained in any forward-looking statements. The Private Securities Litigation Reform Act of 1995 and Section 27A of the Securities Act do not protect any forward-looking statements that we make in connection with this offering. All forward-looking statements included in this prospectus and in the documents incorporated by reference in this prospectus are based on information available to us on the date of this prospectus or the date of the applicable document incorporated by reference. Except to the extent required by applicable laws or rules, we undertake no obligation to publicly update or revise any forward-looking statement, whether written or oral, that may be made from time to time, whether as a result of new information, future events or otherwise. All subsequent written and oral forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the cautionary statements contained above and throughout this prospectus and in the documents incorporated by reference in this prospectus. We qualify all of our forward-looking statements by these cautionary statements.

You should rely only on the information in this prospectus. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely upon it.

USE OF PROCEEDS

Unless we inform you otherwise in the prospectus supplement, we will use the net proceeds from the sale of the securities offered by this prospectus and the exercise price from the exercise of any convertible securities, if any, for working capital and general corporate purposes.

When particular securities are offered, the prospectus supplement relating to that offering will set forth our intended use of the net proceeds received from the sale of those securities we sell. Pending the application of the net proceeds for these purposes, we expect to invest the proceeds in short-term, interest-bearing instruments or other investment-grade securities.

THE SECURITIES WE MAY OFFER

The descriptions of the securities contained in this prospectus, together with the applicable prospectus supplements, summarize all of the material terms and provisions of the various types of securities that we may offer. We will describe in the applicable prospectus supplement relating to any securities the particular terms of the securities offered by that prospectus supplement. If we indicate in the applicable prospectus supplement, the terms of the securities may differ from the terms we have summarized below. We may also include in the prospectus supplement information about material United States federal income tax considerations relating to the securities, and the securities exchange, if any, on which the securities will be listed.

We may sell from time to time, in one or more offerings:

In this prospectus, we refer to the common stock, preferred stock, debt securities, subscription rights, warrants and units collectively as “securities.” The total dollar amount of all securities that we may sell will not exceed $100,000,000.

If we issue debt securities at a discount from their original stated principal amount, then, for purposes of calculating the total dollar amount of all securities issued under this prospectus, we will treat the initial offering price of the debt securities as the total original principal amount of the debt securities.

This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.

DESCRIPTION OF CAPITAL STOCK

We have authorized capital stock consisting of 75,000,000 shares of common stock and 10,000,000 shares of preferred stock, par value $0.001 per share, of which 6,040,000 shares have been designated as shares of Series A Preferred Stock and 187,500 have been designated as Series B Convertible Preferred Stock, par value $0.001 per share (“Series B Preferred Stock”), as of April 18, 2025. As of April 17, 2025, we had 12,508,045 shares of common stock issued and outstanding, 4,953,545 shares of Series A Preferred Stock issued and outstanding, and 62,500 shares of Series B Preferred Stock issued and outstanding. Unless stated otherwise, the following discussion summarizes the term and provisions of our articles of incorporation, as amended (the “Articles of Incorporation”), and our bylaws (the “Bylaws”). This description is summarized from, and qualified in its entirety by reference to, our Articles of Incorporation (including the certificate of designation for our Series A Preferred Stock, as amended (the “Series A COD”), and the certificate of designation for the Series B Preferred Stock, as amended (the “Series B COD”)) and our Bylaws, which are filed as exhibits to the registration statement of which this prospectus forms a part, and the applicable provisions of the Nevada Revised Statutes, as amended (the “NRS”).

General

Our Articles of Incorporation authorizes us to issue up to 85,000,000 shares of stock, consisting of 75,000,000 shares of common stock and 10,000,000 shares of preferred stock, of which 6,040,000 shares have been designated as Series A Preferred Stock and 187,500 have been designated as Series B Preferred Stock, as of April 18, 2025.

Under our Articles of Incorporation, our Board, without stockholder approval, is authorized to provide for the issuance of shares of common stock or preferred stock in one or more classes or series, to establish the number of shares in each class or series, and to fix the terms thereof.

Common Stock

Voting rights. The holders of our common stock are entitled to one vote per share held on all matters on which a vote of our common stockholders is taken. Stockholders do not have cumulative voting rights in the election of directors. The election of directors of the Company is decided by plurality vote and all other questions are decided by a majority of the votes cast by our stockholders present in person or by proxy, except as otherwise required by the NRS or our Articles of Incorporation. Our Articles of Incorporation provide that notwithstanding any other provision of our Articles of Incorporation or our Bylaws (and notwithstanding the fact that some lesser percentage may be specified by law, the Articles of Incorporation, or the Bylaws), any director or the entire Board may be removed at any time, but only for cause upon the affirmative vote of 75% or more of the outstanding shares of capital stock entitled to vote for the election of directors at a meeting called for that purpose.

The Board is divided into three classes, with each class consisting, as nearly as may be possible, of one-third of the total number of directors, with the terms of the classes scheduled to expire in successive years. At each annual meeting of the Company’s stockholders, the stockholders elect the members of a single class of directors for three-year terms.

Dividends. The holders of our common stock are entitled to receive dividends when, as, and if declared by the Board, out of funds legally available therefor.

Liquidation. Except as otherwise provided under our Articles of Incorporation (including the terms of any preferred stock), upon liquidation, dissolution, or the winding up of the Company, holders of our common stock are entitled to receive any remaining assets of the Company in proportion to the respective number of shares held after payment of and reservation for Company liabilities.

Preemptive Rights. The holders of shares of our common stock do not have any preemptive right to subscribe for or purchase any shares of any class or series of our capital stock.

Redemption Rights. The outstanding shares of common stock are not subject to redemption by the Company. To the extent that the Company issues additional shares of common stock, the relative interest in the Company of existing stockholders will likely be diluted.

Preferred Stock

Our Articles of Incorporation authorize the Board, without obtaining stockholder approval, to issue up to 10,000,000 shares of preferred stock, from time to time, in one or more series, and to fix the number of shares and determine for each such series such voting powers, designations, preferences, and relative participating, optional, or other rights and such qualifications, limitations, or restrictions thereof. The Board is also expressly authorized to increase or decrease (but not below the number of such series then outstanding) the number of shares of any series subsequent to the issuance of shares of that series. If the number of shares of any series is decreased, the shares no longer designated as shares of such series will resume the status of “blank check” preferred stock and may be designated, again, as a new series of preferred stock by the Board.

As of April 18, 2025, 6,040,000 shares of our preferred stock were designated as shares of Series A Preferred Stock and 187,500 shares were designated as Series B Preferred Stock. Unless the applicable prospectus supplement indicates otherwise, we will have the right to “reopen” a previous issue of a series of preferred stock by issuing additional preferred stock of such series.

Series A Preferred Stock

The following is a summary of some general terms and provisions of our Series A Preferred Stock. Because it is a summary, it does not contain all of the information that may be important to you. If you want more information, you should read our Articles of Incorporation (including the Series A COD and Series B COD) and Bylaws, copies of which are filed as exhibits to this prospectus.

Voting Rights. Holders of the Series A Preferred Stock do not have any voting rights, except as described below or as otherwise required by law. In any matter in which the Series A Preferred Stock may vote (as expressly provided in the Series A COD or as may be required by law), each share of Series A Preferred Stock will be entitled to one vote per $25.00 of liquidation preference; provided that if the Series A Preferred Stock and any other stock ranking on parity to the Series A Preferred Stock as to dividend rights and rights as to the distribution of assets upon the Company’s liquidation, dissolution or winding up are entitled to vote together as a single class on any matter, the holders of each will vote in proportion to their respective liquidation preferences.

Dividends. Subject to the preferential rights, if any, of the holders of any class or series of capital stock of the Company ranking senior to the Series A Preferred Stock as to dividends, the holders of the Series A Preferred Stock are entitled to receive, when, as and if declared by the Board (or a duly authorized committee of the Board), only out of funds legally available for the payment of dividends, cumulative cash dividends at the annual rate of 9.0% of the $25.00 liquidation preference per year (equivalent to $2.25 per year).

Liquidation. In the event of the voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company, holders of shares of Series A Preferred Stock will be entitled to be paid out of the assets of the Company legally available for distribution to its stockholders (i.e., after satisfaction of all the Company’s liabilities to creditors, if any) and, subject to the rights of holders of any shares of each other class or series of capital stock ranking, as to rights to the distribution of assets upon the Company’s voluntary or involuntary liquidation, dissolution or winding up, senior to the Series A Preferred Stock, a liquidation preference of $25.00 per share, plus an amount equal to any accumulated and unpaid dividends to the date of payment (whether or not declared), before any distribution or payment may be made to holders of shares of our common stock or any other class or series of the Company’s capital stock ranking, as to rights to the distribution of assets upon any voluntary or involuntary liquidation, dissolution or winding up, junior to the Series A Preferred Stock (the “liquidation preference”).

If, upon such voluntary or involuntary liquidation, dissolution or winding up of the Company’s affairs, the assets of the Company legally available for distribution to the Company’s stockholders are insufficient to pay the full amount of the liquidation preference on all outstanding shares of Series A Preferred Stock and the corresponding amounts payable on all shares of each other class or series of capital stock of the Company ranking, as to rights to the distribution of assets upon any voluntary or involuntary liquidation, dissolution or winding up, on parity with the Series A Preferred Stock, then the holders of the Series A Preferred Stock and each such other class or series of capital stock of the Company ranking, as to rights to the distribution of assets upon the Company’s voluntary or involuntary liquidation, dissolution or winding up, on parity with the Series A Preferred Stock will share ratably in any distribution of assets in proportion to the full liquidation preference to which they would otherwise be respectively entitled.

Preemptive Rights. Holders of Series A Preferred Stock do not, as holders of Series A Preferred Stock, have any preemptive rights to purchase or subscribe for our common stock or any other security of the Company.

Redemption Rights. The Company is not required to redeem the Series A Preferred Stock at any time. The Series A Preferred Stock is perpetual and has no maturity date. On or after August 26, 2025, the Series A Preferred Stock may be redeemed at the Company’s option, in whole or in part, from time to time, at a redemption price of $25.00 per share, plus all dividends accumulated and unpaid (whether or not declared) on the Series A Preferred Stock up to, but not including, the date of such redemption. The Company also has a special optional right to redeem the Series A Preferred Stock, by paying a redemption price of $25.00 per share, plus all dividends accumulated and unpaid(whether or not declared) on the Series A Preferred Stock up to, but not including, the date of such redemption, if a Delisting Event or Change of Control (each as defined in the Series A COD) occurs. The Series A Preferred Stock is not subject to any sinking fund.

Conversion Rights. The shares of Series A Preferred Stock are not convertible into or exchangeable for any other property or securities of the Company or any other entity, except upon the occurrence of a Delisting Event or Change of Control (each as defined in the Series A COD), in which case (unless the Company has already elected to redeem such shares), shares of Series A Preferred Stock are convertible into shares of our common stock (or equivalent value of alternative consideration), as calculated pursuant to the terms of the Series A COD.

Ranking. The Series A Preferred Stock will, as to dividend rights and rights as to the distribution of assets upon the Company’s liquidation, dissolution or winding up, rank: (1) senior to all classes or series of our common stock and to all other capital stock issued by the Company expressly designated as ranking junior to the Series A Preferred Stock, (2) on parity with any future class or series of the Company’s capital stock expressly designated as ranking on parity with the Series A Preferred Stock; (3) junior to any future class or series of the Company capital stock expressly designated as ranking senior to the Series A Preferred Stock; and (4) junior to all the Company’s existing and future indebtedness (including subordinated indebtedness and any indebtedness convertible into common stock or preferred stock) and other liabilities with respect to assets available to satisfy claims against the Company and structurally subordinated to the indebtedness and other liabilities of (as well as any preferred equity interests held by others in) existing or future subsidiaries of the Company. The Company may issue junior capital stock and parity capital stock, as described above, at any time and from time to time in one or more series without the consent of the holders of the Series A Preferred Stock. The Company may not issue any senior capital stock, as described above, without the consent or affirmative vote of the holders of at least two-thirds of the outstanding shares of Series A Preferred Stock and each other class or series of our preferred stock entitled to vote thereon, voting as a single class.

Series B Preferred Stock

The following is a summary of some general terms and provisions of our Series B Preferred Stock. Because it is a summary, it does not contain all of the information that may be important to you. If you want more information, you should read our Articles of Incorporation (including the Series A COD and Series B COD) and Bylaws, copies of which are filed as exhibits to this prospectus.

Redemption Rights. The Series B Preferred Stock is perpetual and has no maturity date. Provided that no shares of Series A Preferred Stock are outstanding, either the Company or the holder may, at its option, at any time on or after the later of (i) the third anniversary of the Original Issue Date and (ii) Note Release Date (each as defined in the Series B COD and together, the “Redemption Date”), if all of the shares of Series B Preferred Stock have not been converted to shares of common stock prior to the Redemption Date, redeem the outstanding shares of Series B Preferred Stock, in whole or in part, at any time after the Redemption Date, at a cash redemption price per share of Series B Preferred Stock equal to the Stated Value, or $100.00. In the event that our common stock ceases to trade on a national exchange for twenty consecutive Trading Days, if at least a majority of the holders so elect, they may present the Company with a Notice of Redemption. The Series B Preferred Stock is not subject to any mandatory redemption, sinking fund or other similar provisions.

Conversion Rights. Each share of Series B Preferred Stock shall be convertible, at any time and from time to time on or after the later of a date that is (i) 180 days after the Original Issue Date (as defined in the Series B COD) or (ii) the date on which those certain senior secured convertible notes in the original aggregate principal amount of $16,304,348 that were issued on or about October 25, 2021 have been fully redeemed, defeased, or converted, at the option of the holder thereof, into that number of shares of our common stock determined by dividing the Stated Value of such share of Series B Preferred Stock by the Conversion Price (as defined below). Holders shall also be paid any accrued and unpaid cash dividends and/or issued shares of our common stock, if dividends are payable in shares of our common stock, based on the applicable rate of conversion, at the same time such shares are issued to the holders. If a Fundamental Transaction (as defined in the Series B COD) occurs, then immediately prior to the closing of such Fundamental Transaction, each share of Series B Preferred Stock shall, without further action from the holder thereof, automatically convert into common stock at the then effective conversion rate, without regard to any beneficial ownership limitation under the Series B COD.

Conversion Price. The conversion price for the Series B Preferred Stock shall equal $5.00 (the “Conversion Price”), subject to adjustment for reverse and forward stock splits, stock dividends, stock combinations and other similar transactions of our common stock that occur after the First Amendment Effective Date (as defined in the Series B COD). The Conversion Price shall be subject to adjustment on the Lockup Expiration Date (as defined in the Series B COD) as follows: the lowest of (a) $5.00; (b) the closing price of our common stock on the Trading Day immediately preceding the Lockup Expiration Date, as quoted on a Trading Market; or (c) 90% of the average VWAP for the five Trading Days preceding the Lockup Expiration Date. The Conversion Price shall be rounded down to the nearest $0.01.

Dividends. Holders of Series B Preferred Stock shall be entitled to receive, and the Company shall pay, by issuing shares of our common stock (or cash at the Company’s option) to such holders, dividends on shares of Series B Preferred Stock, based on the Stated Value, at a rate of ten percent (10%) per annum, commencing on the Original Issue Date (as defined in the Series B COD) until the date that such share of Series B Preferred Stock is converted to common stock or otherwise redeemed (the “Dividend Termination Date”). Such dividends shall accrue and be compounded daily on the basis of a 360-day day year and twelve 30-day months and shall be paid annually on each anniversary of the Original Issue Date (or within five (business days thereof) and, in the event that shares of Series B Preferred Stock are converted to common stock or otherwise redeemed, on the Dividend Termination Date (or within five (5) business days thereof). No other dividends shall be paid on shares of Series B Preferred Stock.

Voting Rights. Series B Preferred Stock will vote with the shares of common stock, on an as-converted to common stock basis, with respect to all matters on which the holders of common stock are entitled to vote, provided, that no holder (together with such holder’s Affiliates and Attribution Parties (each as defined in the Series B COD) shall be entitled to vote an amount of shares of common stock (including Series B Preferred Stock on as an-converted to common stock basis) in excess of the Beneficial Ownership Limitation (as defined in the Series B COD), with any remaining amount of shares held by such holder, its Affiliates and Attribution Parties deemed non-voting. In addition, as long as any shares of Series B Preferred Stock are outstanding, the Company shall not, without the affirmative vote of the holders of a majority of the then outstanding shares of the Series B Preferred Stock, (a) alter or change adversely the powers, preferences or rights given to the Series B Preferred Stock or alter or amend the Series B COD, (b) amend its Articles of Incorporation or other charter documents in any manner that adversely affects any rights of the holders, (c) increase the number of authorized shares of preferred stock, or (d) enter into any agreement with respect to any of the foregoing.

Liquidation Rights. Upon any liquidation, dissolution or winding-up of the Company, whether voluntary or involuntary (a “Liquidation”), the holders of Series B Preferred Stock shall be entitled to receive out of the assets, whether capital or surplus, of the Company the greater of the following amounts:

(a) the aggregate Stated Value of such holder’s shares of Series B Preferred Stock; or

(b) the amount the holder would be entitled to receive if the Series B Preferred Stock were fully converted (disregarding for such purposes any conversion limitations hereunder) to common stock, which amounts shall be paid pari passu with all holders of common stock.

In addition, in the case of either (a) or (b) above, the holders will be entitled to the payment of all accrued and unpaid dividends on the Series B Preferred Stock and, in the event any of such dividends are payable in shares of common stock, the cash value of such shares of common stock upon Liquidation. The Company shall mail written notice of any such Liquidation, not less than forty-five (45) days prior to the payment date stated therein, to each holder.

Ranking. Except to the extent that the holders of at least a majority of the outstanding Series B Preferred Stock (the “Required Holders”) expressly consent to the creation of Parity Stock (as defined below) or Senior Preferred Stock (as defined below), all shares of common stock and all shares of capital stock of the Company authorized or designated after the date of the designation of the Series B Preferred Stock shall be junior in rank to the Series B Preferred Stock with respect to the preferences as to dividends, distributions and payments upon the liquidation, dissolution and winding up of the Company (such junior stock collectively, “Junior Stock”). Without limiting any other provision of the Series B COD, without the prior express consent of the Required Holders, voting separate as a single class, the Company shall not hereafter authorize or issue any additional or other shares of capital stock that is (i) of senior rank to the Series B Preferred Stock in respect of the preferences as to dividends, distributions and payments upon the liquidation, dissolution and winding up of the Company (collectively, “Senior Preferred Stock”); provided, however, that the Series B Preferred Stock shall be pari passu to the Series A Preferred Stock, including any Series A Preferred Stock that shall be issued subsequent to the designation of the Series B Preferred Stock, or (ii) of pari passu rank to the Series B Preferred Stock in respect of the preferences as to dividends, distributions and payments upon the liquidation, dissolution and winding up of the Company (collectively, the “Parity Stock”).

Terms of the Preferred Stock That We May Offer and Sell to You

We summarize below some of the provisions that will apply to the preferred stock that we may offer to you unless the applicable prospectus supplement provides otherwise. This summary may not contain all information that is important to you. You should read the prospectus supplement, which will contain additional information and which may update or change some of the information below. Prior to the issuance of a new series of preferred stock, we will further amend our articles of incorporation, as amended, by filing a certificate of designation designating the stock of that series and the terms of that series. We will file a copy of the certificate of designation that contains the terms of each new series of preferred stock with the Nevada Secretary of State and the SEC each time we issue a new series of preferred stock. Each certificate of designation will establish the number of shares included in a designated series and fix the designation, powers, privileges, preferences and rights of the shares of each series as well as any applicable qualifications, limitations or restrictions. You should refer to the applicable certificate of designation as well as our articles of incorporation, as amended, before deciding to buy shares of our preferred stock as described in the applicable prospectus supplement.

Our board of directors has the authority, without further action by the stockholders, to issue preferred stock in one or more series and to fix the number of shares, dividend rights, conversion rights, voting rights, redemption rights, liquidation preferences, sinking funds, and any other rights, preferences, privileges and restrictions applicable to each such series of preferred stock. The issuance of any preferred stock could adversely affect the rights of the holders of common stock and, therefore, reduce the value of the common stock. The ability of our board of directors to issue preferred stock could discourage, delay or prevent a takeover or other corporate action. The terms of any particular series of preferred stock will be described in the prospectus supplement relating to that particular series of preferred stock, including, where applicable:

Anti-Takeover Effects of Certain Provisions of Our Articles of Incorporation and Bylaws, and Nevada Law

Our Articles of Incorporation and Bylaws contain provisions and terms that may delay, defer, or prevent a tender offer or change in control of the Company that a stockholder might consider to be in his, her, or its best interests, including attempts that might result in a premium being paid over the market price for shares of our Common Stock. The Company expects that such provisions and terms may have the effect of discouraging extraordinary corporate transactions with respect to the Company, such as hostile takeover bids, and will instead encourage any potential acquiror of the Company to first correspond with our Board. These provisions and terms include:

Nevada’s “combinations with interested stockholders” statutes, NRS 78.411 through 78.444, inclusive, prohibit specified types of business “combinations” between certain Nevada corporations and any person deemed to be an “interested stockholder” for two years after such person first becomes an “interested stockholder” unless the corporation’s board of directors approves the combination (or the transaction by which such person becomes an “interested stockholder”) in advance, or unless the combination is approved by the board of directors and sixty percent of the corporation’s voting power not beneficially owned by the interested stockholder, its affiliates and associates. Further, in the absence of prior approval certain restrictions may apply even after such two year period. However, these statutes do not apply to any combination of a corporation and an interested stockholder after the expiration of four years after the person first became an interested stockholder. For purposes of these statutes, an “interested stockholder” is any person who is (1) the beneficial owner, directly or indirectly, of ten percent or more of the voting power of the outstanding voting shares of the corporation, or (2) an affiliate or associate of the corporation and at any time within the two previous years was the beneficial owner, directly or indirectly, of ten percent or more of the voting power of the then outstanding shares of the corporation. The definition of the term “combination” is sufficiently broad to cover most significant transactions between a corporation and an “interested stockholder.” These statutes generally apply to Nevada corporations with 200 or more stockholders of record. However, a Nevada corporation may elect in its articles of incorporation not to be governed by these particular laws, but if such election is not made in the corporation’s original articles of incorporation, the amendment (1) must be approved by the affirmative vote of the holders of stock representing a majority of the outstanding voting power of the corporation not beneficially owned by interested stockholders or their affiliates and associates, and (2) is not effective until 18 months after the vote approving the amendment and does not apply to any combination with a person who first became an interested stockholder on or before the effective date of the amendment. We made an election to opt out of these statutes in our original articles of incorporation and have not amended such provision.

Nevada’s “acquisition of controlling interest” statutes (NRS 78.378 through 78.3793, inclusive) contain provisions governing the acquisition of a controlling interest in certain Nevada corporations. These “control share” laws provide generally that any person that acquires a “controlling interest” in certain Nevada corporations may be denied voting rights, unless a majority of the disinterested stockholders of the corporation elect to restore such voting rights. These laws will apply to us as of a particular date if we were to have 200 or more stockholders of record (at least 100 of whom have addresses in Nevada appearing on our stock ledger at all times during the 90 days immediately preceding that date) and do business in the State of Nevada directly or through an affiliated corporation, unless our Articles of Incorporation or Bylaws in effect on the tenth day after the acquisition of a controlling interest provide otherwise. These laws provide that a person acquires a “controlling interest” whenever a person acquires shares of a subject corporation that, but for the application of these provisions of the NRS, would enable that person to exercise (1) one-fifth or more, but less than one-third, (2) one-third or more, but less than a majority, or (3) a majority or more of all of the voting power of the corporation in the election of directors. Once an acquirer crosses one of these thresholds, shares which it acquired in the transaction taking it over the threshold and within the 90 days immediately preceding the date when the acquiring person acquired or offered to acquire a controlling interest become “control shares” to which the voting restrictions described above apply. These laws may have a chilling effect on certain transactions if our Articles of Incorporation or Bylaws are not timely amended to provide that these provisions do not apply to us or to an acquisition of a controlling interest, or if our disinterested stockholders do not confer voting rights in the control shares.

Further, NRS 78.139 provides that directors may resist a change or potential change in control of a corporation if the board of directors determines that the change or potential change in control is opposed to or not in the best interest of the corporation upon consideration of any relevant facts, circumstances, contingencies or constituencies pursuant to NRS 78.138(4).

We expect the existence of these provisions may have an anti-takeover effect with respect to transactions that our Board does not approve in advance and could result in making it more difficult to accomplish transactions that our stockholders may see as beneficial such as (i) discouraging business combinations that might result in a premium over the market price for the shares of our Common Stock; (ii) discouraging hostile takeovers which could inhibit temporary fluctuations in the market price of our Common Stock that often result from actual or rumored hostile takeover attempts; and (iii) preventing changes in our management.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock, Series A Preferred Stock and Series B Preferred Stock is Equiniti Trust Company, LLC (the “Transfer Agent”) (formerly: American Stock Transfer & Trust Company, LLC). The Transfer Agent’s address is 48 Wall Street, 23rd Floor, New York, NY 10005. The transfer agent and registrar for any additional series or class of preferred stock, if any, will be set forth in each applicable prospectus supplement.

DESCRIPTION OF WARRANTS

We summarize below some of the provisions that will apply to the warrants unless the applicable prospectus supplement provides otherwise. This summary may not contain all information that is important to you. The complete terms of the warrants will be contained in the applicable warrant certificate and warrant agreement. These documents have been or will be included or incorporated by reference as exhibits to the registration statement of which this prospectus is a part. You should read the warrant certificate and the warrant agreement. You should also read the prospectus supplement, which will contain additional information and which may update or change some of the information below.

General

We may issue warrants to purchase our debt or equity securities or securities of third parties or other rights, including rights to receive payment in cash or securities based on the value, rate or price of one or more specified commodities, currencies, securities or indices, or any combination of the foregoing. Warrants may be issued independently or together with any other securities and may be attached to, or separate from, such securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and a bank, trust company or other financial institution, as warrant agent, or we may issue warrants directly to investors. A description of the terms and material provisions of any warrants we may issue will be set forth in the applicable prospectus supplement.

The applicable prospectus supplement will describe the following terms of any warrants in respect of which this prospectus is being delivered:

Transfer Agent and Registrar

The transfer agent and registrar, if any, for any warrants will be set forth in the applicable prospectus supplement.

DESCRIPTION OF DEBT SECURITIES

This prospectus describes certain general terms and provisions of debt securities that we may offer. The debt securities may be issued pursuant to, in the case of senior debt securities, a senior indenture, and in the case of subordinated debt securities, a subordinated indenture, in each case in the forms filed as exhibits to this registration statement, which we refer to as the “indentures.” The indentures will be entered into between us and a trustee to be named prior to the issuance of any debt securities, which we refer to as the “trustee.” The indentures will not limit the amount of debt securities that can be issued thereunder and will provide that the debt securities may be issued from time to time in one or more series pursuant to the terms of one or more securities resolutions or supplemental indentures creating such series.

We have summarized below the material provisions of the indentures and the debt securities or indicated which material provisions will be described in the related prospectus supplement for any offering of debt securities. These descriptions are only summaries, and you should refer to the relevant indenture for the particular offering of debt securities itself which will describe completely the terms and definitions of the offered debt securities and contain additional information about the debt securities.

All references in this section, “Description of Debt Securities,” to “Soluna,” the “Company”, “we”, “us”, “our”, the “registrant” or similar words are solely to Soluna Holdings, Inc., and not to its subsidiaries.

Terms

When we offer to sell a particular series of debt securities, we will describe the specific terms of the securities in a prospectus supplement. The prospectus supplement will set forth the following terms, as applicable, of the debt securities offered thereby:

Debt securities of any series may be issued as registered debt securities or uncertificated debt securities, in such denominations as specified in the terms of the series.

Securities may be issued under the indentures as Discounted Debt Securities to be offered and sold at a substantial discount from the principal amount thereof. Special United States federal income tax and other considerations applicable thereto will be described in the prospectus supplement relating to such Discounted Debt Securities. “Discounted Debt Security” means a security where the amount of principal due upon acceleration is less than the stated principal amount.

We are not obligated to issue all debt securities of one series at the same time and, unless otherwise provided in the prospectus supplement, we may reopen a series, without the consent of the holders of the debt securities of that series, for the issuance of additional debt securities of that series. Additional debt securities of a particular series will have the same terms and conditions as outstanding debt securities of such series, except for the date of original issuance and the offering price, and will be consolidated with, and form a single series with, such outstanding debt securities.

Ranking

The senior debt securities will rank equally with all of our other senior and unsubordinated debt. Our secured debt, if any, will be effectively senior to the senior debt securities to the extent of the value of the assets securing such debt. The subordinated debt securities will be subordinate and junior in right of payment to all of our present and future senior indebtedness to the extent and in the manner described in the prospectus supplement and as set forth in the board resolution, officer’s certificate or supplemental indenture relating to such offering.

We have only a stockholder’s claim on the assets of our subsidiaries. This stockholder’s claim is junior to the claims that creditors of our subsidiaries have against our subsidiaries. Holders of our debt securities will be our creditors and not creditors of any of our subsidiaries. As a result, all the existing and future liabilities of our subsidiaries, including any claims of their creditors, will effectively be senior to the debt securities with respect to the assets of our subsidiaries. In addition, to the extent that we issue any secured debt, the debt securities will be effectively subordinated to such secured debt to the extent of the value of the assets securing such secured debt.

The debt securities will be obligations exclusively of Soluna Holdings, Inc. To the extent that our ability to service our debt, including the debt securities, may be dependent upon the earnings of our subsidiaries, our ability to do so will be dependent on the ability of our subsidiaries to distribute those earnings to us as dividends, loans or other payments.

Certain Covenants

Any covenants that may apply to a particular series of debt securities will be described in the prospectus supplement relating thereto.

Successor Obligor

The indentures provide that, unless otherwise specified in the securities resolution or supplemental indenture establishing a series of debt securities, we shall not consolidate with or merge into, or transfer all or substantially all of our assets to, any person in any transaction in which we are not the survivor, unless:

In such event, the successor will be substituted for us, and thereafter all of our obligations under the relevant indenture, the debt securities and any coupons will terminate.

The indentures provide that these limitations shall not apply if our Board makes a good faith determination that the principal purpose of the transaction is to change our state of incorporation.

Exchange of Debt Securities

Registered debt securities may be exchanged for an equal aggregate principal amount of registered debt securities of the same series and date of maturity in such authorized denominations as may be requested upon surrender of the registered debt securities at an agency of the Company maintained for such purpose and upon fulfillment of all other requirements of such agent.

Default and Remedies

Unless the securities resolution or supplemental indenture establishing the series otherwise provides (in which event the prospectus supplement will so state), an “Event of Default” with respect to a series of debt securities will occur if:

The term “Bankruptcy Law” means Title 11 of the United States Code or any similar Federal or State law for the relief of debtors. The term “Custodian” means any receiver, trustee, assignee, liquidator or a similar official under any Bankruptcy Law.

“Default” means any event which is, or after notice or passage of time would be, an Event of Default. A Default under subparagraph (3) above is not an Event of Default until the trustee or the holders of at least 25% in principal amount of the series notify us of the Default and we do not cure the Default within the time specified after receipt of the notice.

The trustee may require indemnity satisfactory to it before it enforces the indentures or the debt securities of the series. Subject to certain limitations, holders of a majority in principal amount of the debt securities of the series may direct the trustee in its exercise of any trust or power with respect to such series. Except in the case of Default in payment on a series, the trustee may withhold from securityholders of such series notice of any continuing Default if the trustee determines that withholding notice is in the interest of such securityholders. We are required to furnish the trustee annually a brief certificate as to our compliance with all conditions and covenants under the indentures.

The indentures do not have cross-default provisions. Thus, a default by us on any other debt, including any other series of debt securities, would not constitute an Event of Default.

Amendments and Waivers

The indentures and the debt securities or any coupons of the series may be amended, and any Default may be waived as follows:

Unless the securities resolution or supplemental indenture otherwise provides (in which event the applicable prospectus supplement will so state), the debt securities and the indentures may be amended with the consent of the holders of a majority in principal amount of the debt securities of all series affected voting as one class. Unless the securities resolution or supplemental indenture otherwise provides (in which event the applicable prospectus supplement will so state), a Default other than a Default in payment on a particular series may be waived with the consent of the holders of a majority in principal amount of the debt securities of the series. However, without the consent of each securityholder affected, no amendment or waiver may:

Without the consent of any securityholder, the indentures or the debt securities may be amended to:

Conversion Rights

Any securities resolution or supplemental indenture establishing a series of debt securities may provide that the debt securities of such series will be convertible at the option of the holders thereof into or for our common stock or other equity or debt instruments. The securities resolution or supplemental indenture may establish, among other things, (1) the number or amount of shares of common stock or other equity or debt instruments for which $1,000 aggregate principal amount of the debt securities of the series is convertible, as may be adjusted pursuant to the terms of the relevant indenture and the securities resolution; and (2) provisions for adjustments to the conversion rate and limitations upon exercise of the conversion right. The indentures provide that we will not be required to make an adjustment in the conversion rate unless the adjustment would require a cumulative change of at least 1% in the conversion rate. However, we will carry forward any adjustments that are less than 1% of the conversion rate and take them into account in any subsequent adjustment of the conversion rate.

Legal Defeasance and Covenant Defeasance

Debt securities of a series may be defeased in accordance with their terms and, unless the securities resolution or supplemental indenture establishing the terms of the series otherwise provides, as set forth below. We at any time may terminate as to a series all of our obligations (except for certain obligations, including obligations with respect to the defeasance trust and obligations to register the transfer or exchange of a debt security, to replace destroyed, lost or stolen debt securities and coupons and to maintain paying agencies in respect of the debt securities) with respect to the debt securities of the series and any related coupons and the relevant indenture, which we refer to as legal defeasance. We at any time may terminate as to a series our obligations with respect to any restrictive covenants which may be applicable to a particular series, which we refer to as covenant defeasance.

We may exercise our legal defeasance option notwithstanding our prior exercise of our covenant defeasance option. If we exercise our legal defeasance option, a series may not be accelerated because of an Event of Default. If we exercise our covenant defeasance option, a series may not be accelerated by reference to any covenant which may be applicable to a series.

To exercise either defeasance option as to a series, we must (1) irrevocably deposit in trust with the trustee (or another trustee) money or U.S. Government Obligations (as defined below), deliver a certificate from a nationally recognized firm of independent accountants expressing their opinion that the payments of principal and interest when due on the deposited U.S. Government Obligations, without reinvestment, plus any deposited money without investment will provide cash at such times and in such amounts as will be sufficient to pay the principal and interest when due on all debt securities of such series to maturity or redemption, as the case may be; and (2) comply with certain other conditions. In particular, we must obtain an opinion of tax counsel that the defeasance will not result in recognition of any gain or loss to holders for federal income tax purposes.

“U.S. Government Obligations” means direct obligations of the United States or any agency or instrumentality of the United States, the payment of which is unconditionally guaranteed by the United States, which, in either case, have the full faith and credit of the United States pledged for payment and which are not callable at the issuer’s option, or certificates representing an ownership interest in such obligations.

Regarding the Trustee

Unless otherwise indicated in a prospectus supplement, the trustee will also act as depository of funds, transfer agent, paying agent and conversion agent, as applicable, with respect to the debt securities. In certain circumstances, we or the securityholders may remove the trustee as the trustee under a given indenture. The indenture trustee may also provide additional unrelated services to us as a depository of funds, registrar, trustee and similar services.

Governing Law

The indentures and the debt securities will be governed by New York law, except to the extent that the Trust Indenture Act of 1939 is applicable.

DESCRIPTION OF SUBSCRIPTION RIGHTS

We may issue subscription rights to purchase our equity or debt securities. These subscription rights may be offered independently or together with any other security offered hereby and may or may not be transferable by the stockholder receiving the subscription rights in such offering. In connection with any offering of subscription rights, we may enter into a standby arrangement with one or more underwriters or other purchasers pursuant to which the underwriters or other purchasers may be required to purchase any securities remaining unsubscribed for after such offering.

The prospectus supplement relating to any subscription rights we offer, if any, will, to the extent applicable, include specific terms relating to the offering, including some or all of the following:

DESCRIPTION OF UNITS

We may issue units comprised of one or more of the other securities described in this prospectus in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security (but, to the extent convertible securities are included in the units, the holder of the units will be deemed the holder of the convertible securities and not the holder of the underlying securities). The unit agreement under which a unit is issued, if any, may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date. The applicable prospectus supplement may describe:

This summary of certain general terms of units and any summary description of units in the applicable prospectus supplement do not purport to be complete and are qualified in their entirety by reference to all provisions of the applicable unit agreement and, if applicable, collateral arrangements and depositary arrangements relating to such units. The forms of the unit agreements and other documents relating to a particular issue of units will be filed with the SEC each time we issue units, and you should read those documents for provisions that may be important to you.

FORMS OF SECURITIES

Each debt security and, to the extent applicable, warrant, subscription right and unit, will be represented either by a certificate issued in definitive form to a particular investor or by one or more global securities representing the entire issuance of securities. Certificated securities in definitive form and global securities will be issued in registered form. Definitive securities name you or your nominee as the owner of the security, and in order to transfer or exchange these securities or to receive payments other than interest or other interim payments, you or your nominee must physically deliver the securities to the trustee, registrar, paying agent or other agent, as applicable. Global securities name a depositary or its nominee as the owner of the debt securities or warrants represented by these global securities. The depositary maintains a computerized system that will reflect each investor’s beneficial ownership of the securities through an account maintained by the investor with its broker/dealer, bank, trust company or other representative, as we explain more fully below.

Global Securities

Registered Global Securities. We may issue the registered debt securities and, to the extent applicable, warrants, subscription rights and units in the form of one or more fully registered global securities that will be deposited with a depositary or its nominee identified in the applicable prospectus supplement and registered in the name of that depositary or nominee. In those cases, one or more registered global securities will be issued in a denomination or aggregate denominations equal to the portion of the aggregate principal or face amount of the securities to be represented by registered global securities. Unless and until it is exchanged in whole for securities in definitive registered form, a registered global security may not be transferred except as a whole by and among the depositary for the registered global security, the nominees of the depositary or any successors of the depositary or those nominees.

If not described below, any specific terms of the depositary arrangement with respect to any securities to be represented by a registered global security will be described in the prospectus supplement relating to those securities. We anticipate that the following provisions will apply to all depositary arrangements.

Ownership of beneficial interests in a registered global security will be limited to persons, called participants, that have accounts with the depositary or persons that may hold interests through participants. Upon the issuance of a registered global security, the depositary will credit, on its book-entry registration and transfer system, the participants’ accounts with the respective principal or face amounts of the securities beneficially owned by the participants. Any dealers, underwriters or agents participating in the distribution of the securities will designate the accounts to be credited. Ownership of beneficial interests in a registered global security will be shown on, and the transfer of ownership interests will be effected only through, records maintained by the depositary, with respect to interests of participants, and on the records of participants, with respect to interests of persons holding through participants. The laws of some states may require that some purchasers of securities take physical delivery of these securities in definitive form. These laws may impair your ability to own, transfer or pledge beneficial interests in registered global securities.

So long as the depositary, or its nominee, is the registered owner of a registered global security, that depositary or its nominee, as the case may be, will be considered the sole owner or holder of the securities represented by the registered global security for all purposes under the applicable indenture or warrant agreement. Except as described below, owners of beneficial interests in a registered global security will not be entitled to have the securities represented by the registered global security registered in their names, will not receive or be entitled to receive physical delivery of the securities in definitive form and will not be considered the owners or holders of the securities under the applicable indenture or warrant agreement. Accordingly, each person owning a beneficial interest in a registered global security must rely on the procedures of the depositary for that registered global security and, if that person is not a participant, on the procedures of the participant through which the person owns its interest, to exercise any rights of a holder under the applicable indenture or warrant agreement. We understand that under existing industry practices, if we request any action of holders or if an owner of a beneficial interest in a registered global security desires to give or take any action that a holder is entitled to give or take under the applicable indenture or warrant agreement, the depositary for the registered global security would authorize the participants holding the relevant beneficial interests to give or take that action, and the participants would authorize beneficial owners owning through them to give or take that action or would otherwise act upon the instructions of beneficial owners holding through them. Principal, premium, if any, and interest payments on debt securities and any payments to holders with respect to warrants represented by a registered global security registered in the name of a depositary or its nominee will be made to the depositary or its nominee, as the case may be, as the registered owner of the registered global security. None of the Company, the trustees, the warrant agents or any other agent of the Company, agent of the trustees or agent of the warrant will have any responsibility or liability for any aspect of the records relating to payments made on account of beneficial ownership interests in the registered global security or for maintaining, supervising or reviewing any records relating to those beneficial ownership interests.

We expect that the depositary for any of the securities represented by a registered global security, upon receipt of any payment of principal, premium, interest or other distribution of underlying securities or other property to holders on that registered global security, will immediately credit participants’ accounts in amounts proportionate to their respective beneficial interests in that registered global security as shown on the records of the depositary. We also expect that payments by participants to owners of beneficial interests in a registered global security held through participants will be governed by standing customer instructions and customary practices, as is now the case with the securities held for the accounts of customers in bearer form or registered in “street name,” and will be the responsibility of those participants.

If the depositary for any of these securities represented by a registered global security is at any time unwilling or unable to continue as depositary or ceases to be a clearing agency registered under the Exchange Act and a successor depositary registered as a clearing agency under the Exchange Act is not appointed by us within 90 days, we will issue securities in definitive form in exchange for the registered global security that had been held by the depositary. Any securities issued in definitive form in exchange for a registered global security will be registered in the name or names that the depositary gives to the relevant trustee or warrant agent or other relevant agent of ours or theirs. It is expected that the depositary’s instructions will be based upon directions received by the depositary from participants with respect to ownership of beneficial interests in the registered global security that had been held by the depositary.

PLAN OF DISTRIBUTION

Initial Offering and Sale of Securities

Unless otherwise set forth in a prospectus supplement accompanying this prospectus, we may sell the securities being offered hereby, from time to time, by one or more of the following methods:

Offerings of securities covered by this prospectus also may be made into an existing trading market for those securities in transactions at other than a fixed price, either:

Those at-the-market offerings, if any, will be conducted by underwriters acting as principal or agent of the Company, who may also be third-party sellers of securities as described above. The prospectus supplement with respect to the offered securities will set forth the terms of the offering of the offered securities, including:

The distribution of the securities may be effected from time to time in one or more transactions:

Each prospectus supplement will set forth the manner and terms of an offering of securities including:

In addition, we may enter into derivative or hedging transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. The applicable prospectus supplement may indicate, in connection with such a transaction, that the third parties may sell securities covered by and pursuant to this prospectus and an applicable prospectus supplement. If so, the third party may use securities pledged by us or borrowed from us or others to settle such sales and may use securities received from us to close out any related short positions. We may also loan or pledge securities covered by this prospectus and an applicable prospectus supplement to third parties, who may sell the loaned securities or, in an event of default in the case of a pledge, sell the pledged securities pursuant to this prospectus and the applicable prospectus supplement.

Sales Through Underwriters

If underwriters are used in the sale of some or all of the securities covered by this prospectus, the underwriters will acquire the securities for their own account. The underwriters may resell the securities, either directly to the public or to securities dealers, at various times in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the securities will be subject to certain conditions. Unless indicated otherwise in a prospectus supplement, the underwriters will be obligated to purchase all the securities of the series offered if any of the securities are purchased.

Any public offering price and any concessions allowed or reallowed to dealers may be changed intermittently.

Sales Through Agents

Unless otherwise indicated in the applicable prospectus supplement, when securities are sold through an agent, the designated agent will agree, for the period of its appointment as agent, to use specified efforts to sell the securities for our account and will receive commissions from us as will be set forth in the applicable prospectus supplement.

Securities bought in accordance with a redemption or repayment under their terms also may be offered and sold, if so indicated in the applicable prospectus supplement, in connection with a remarketing by one or more firms acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its agreement, if any, with us and its compensation will be described in the prospectus supplement. Remarketing firms may be deemed to be underwriters in connection with the securities remarketed by them.

If so indicated in the applicable prospectus supplement, we may authorize agents, underwriters or dealers to solicit offers by certain specified institutions to purchase securities at a price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a future date specified in the prospectus supplement. These contracts will be subject only to those conditions set forth in the applicable prospectus supplement, and the prospectus supplement will set forth the commissions payable for solicitation of these contracts.

Direct Sales

We may also sell offered securities directly to institutional investors or others. In this case, no underwriters or agents would be involved. The terms of such sales will be described in the applicable prospectus supplement.

General Information

Broker-dealers, agents or underwriters may receive compensation in the form of discounts, concessions or commissions from us and/or the purchasers of securities for whom such broker-dealers, agents or underwriters may act as agents or to whom they sell as principal, or both. This compensation to a particular broker-dealer might be in excess of customary commissions.

Underwriters, dealers and agents that participate in any distribution of the offered securities may be deemed “underwriters” within the meaning of the Securities Act so any discounts or commissions they receive in connection with the distribution may be deemed to be underwriting compensation. Those underwriters and agents may be entitled, under their agreements with us, to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, or to contribution by us to payments that they may be required to make in respect of those civil liabilities. Certain of those underwriters or agents may be customers of, engage in transactions with, or perform services for, us or our affiliates in the ordinary course of business. We will identify any underwriters or agents, and describe their compensation, in a prospectus supplement. Any institutional investors or others that purchase offered securities directly, and then resell the securities, may be deemed to be underwriters, and any discounts or commissions received by them from us and any profit on the resale of the securities by them may be deemed to be underwriting discounts and commissions under the Securities Act.

We will file a supplement to this prospectus, if required, pursuant to Rule 424(b) under the Securities Act, if we enter into any material arrangement with a broker, dealer, agent or underwriter for the sale of securities through a block trade, special offering, exchange distribution or secondary distribution or a purchase by a broker or dealer. Such prospectus supplement will disclose:

In order to facilitate the offering of certain securities under this prospectus or an applicable prospectus supplement, certain persons participating in the offering of those securities may engage in transactions that stabilize, maintain or otherwise affect the price of those securities during and after the offering of those securities. Specifically, if the applicable prospectus supplement permits, the underwriters of those securities may over-allot or otherwise create a short position in those securities for their own account by selling more of those securities than have been sold to them by us and may elect to cover any such short position by purchasing those securities in the open market.

In addition, the underwriters may stabilize or maintain the price of those securities by bidding for or purchasing those securities in the open market and may impose penalty bids, under which selling concessions allowed to syndicate members or other broker-dealers participating in the offering are reclaimed if securities previously distributed in the offering are repurchased in connection with stabilization transactions or otherwise. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. The imposition of a penalty bid may also affect the price of securities to the extent that it discourages resales of the securities. No representation is made as to the magnitude or effect of any such stabilization or other transactions. Such transactions, if commenced, may be discontinued at any time.

In order to comply with the securities laws of certain states, if applicable, the securities must be sold in such jurisdictions only through registered or licensed brokers or dealers. In addition, in certain states the securities may not be sold unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.

Rule 15c6-1 under the Exchange Act generally requires that trades in the secondary market settle in one business day unless the parties to any such trade expressly agree otherwise. Your prospectus supplement may provide that the original issue date for your securities may be more than one scheduled business day after the trade date for your securities. Accordingly, in such a case, if you wish to trade securities on any date prior to the first business day before the original issue date for your securities, you will be required, by virtue of the fact that your securities initially are expected to settle in more than one scheduled business day after the trade date for your securities, to make alternative settlement arrangements to prevent a failed settlement.

This prospectus, any applicable prospectus supplement and any applicable pricing supplement in electronic format may be made available on the Internet sites of, or through other online services maintained by, us and/or one or more of the agents and/or dealers participating in an offering of securities, or by their affiliates. In those cases, prospective investors may be able to view offering terms online and, depending upon the particular agent or dealer, prospective investors may be allowed to place orders online.

Other than this prospectus, any applicable prospectus supplement and any applicable pricing supplement in electronic format, the information on our website or the website of any agent or dealer, and any information contained in any other website maintained by any agent or dealer:

There can be no assurance that we will sell all or any of the securities offered by this prospectus.

This prospectus may also be used in connection with any issuance of common stock or preferred stock upon exercise of a warrant if such issuance is not exempt from the registration requirements of the Securities Act.

In addition, we may issue the securities as a dividend or distribution or in a subscription rights offering to our existing securityholders. In some cases, we or dealers acting with us or on our behalf may also purchase securities and reoffer them to the public by one or more of the methods described above. This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement.

LEGAL MATTERS

Unless otherwise indicated in the applicable prospectus supplement, the validity of the shares of our capital stock offered hereby will be passed upon for us by Brownstein Hyatt Farber Schreck, LLP, Las Vegas, Nevada, and the validity of the other securities offered hereby will be passed upon for us by Lowenstein Sandler LLP, New York, New York. If the validity of the securities offered hereby in connection with offerings made pursuant to this prospectus are passed upon by counsel for the underwriters, dealers or agents, if any, such counsel will be named in the prospectus supplement relating to such offering.

EXPERTS

The consolidated balance sheets of Soluna Holdings, Inc. and its subsidiaries as of December 31, 2024 and 2023, and the related consolidated statements of operations, changes in equity, and cash flows for each of the years then ended have been audited by UHY LLP, independent registered public accounting firm, as stated in their report which is incorporated herein by reference. Such financial statements have been incorporated herein by reference in reliance on the report of such firm given upon their authority as experts in accounting and auditing.

ADDITIONAL INFORMATION

We have filed with the SEC a registration statement on Form S-3 under the Securities Act with respect to the securities offered by this prospectus. Pursuant to SEC rules, this prospectus, which is part of the registration statement, omits certain information, exhibits, schedules and undertakings set forth in the registration statement. For further information pertaining to us and our securities, reference is made to our SEC filings and to the registration statement and the exhibits and schedules to the registration statement of which this prospectus forms a part. Statements contained in this prospectus as to the contents or provisions of any documents referred to in this prospectus are not necessarily complete, and in each instance where a copy of the document has been filed as an exhibit to the registration statement, reference is made to the exhibit for a more complete description of the matters involved.

In addition, registration statements and certain other filings made with the SEC electronically are publicly available through the SEC’s web site at http://www.sec.gov. The registration statement, including all exhibits and amendments to the registration statement, has been filed electronically with the SEC.

We are subject to the information and periodic reporting requirements of the Exchange Act and, in accordance with such requirements, will file periodic reports, proxy statements, and other information with the SEC. These periodic reports, proxy statements, and other information will be available for inspection and copying at the web site of the SEC referred to above. We also maintain a website at www.solunacomputing.com, at which you may access these materials free of charge as soon as reasonably practicable after they are electronically filed with, or furnished to, the SEC. The information contained in, or that can be accessed through, our website is not part of, and is not incorporated into, this prospectus. We have included our website address in this prospectus solely as an inactive textual reference.

You should rely only on the information in this prospectus and the additional information described above and under the heading “Incorporation of Certain Information by Reference” below. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely upon it. We are not making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information in this prospectus was accurate on the date of the front cover of this prospectus only. Our business, financial condition, results of operations and prospects may have changed since that date.

The representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference into this prospectus were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreement, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to “incorporate by reference” information that we file with it into this prospectus, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus. The information incorporated by reference is considered to be a part of this prospectus, and information that we file later with the SEC will automatically update and supersede information contained in this prospectus and any accompanying prospectus supplement.

We incorporate by reference the documents listed below that we have previously filed with the SEC:

All reports and other documents that we file with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of the initial filing of the registration statement and prior to effectiveness of the registration statement and after the date of this prospectus but prior to the termination of the offering of the securities hereunder will also be considered to be incorporated by reference into this prospectus from the date of the filing of these reports and documents, and will supersede the information herein; provided, however, that all reports, exhibits and other information that we “furnish” to the SEC will not be considered incorporated by reference into this prospectus. Any statement contained in a document incorporated by reference in this prospectus or any prospectus supplement shall be deemed to be modified or superseded to the extent that a statement contained herein, therein or in any other subsequently filed document that also is incorporated by reference herein or therein modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus or any prospectus supplement.

We will provide you without charge, upon your oral or written request, with a copy of any or all reports, proxy statements and other documents we file with the SEC, as well as any or all of the documents incorporated by reference in this prospectus or the registration statement (other than exhibits to such documents unless such exhibits are specifically incorporated by reference into such documents). Requests for such copies should be directed to:

Soluna Holdings, Inc.
325 Washington Avenue Extension
Albany, NY 12205

(518) 218-2550

Attn: Christopher Gandolfo
[email protected]

Up to $3,750,000

Common Stock

PROSPECTUS SUPPLEMENT

H.C. Wainwright & Co.

April 29, 2025