ottr-20250227

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the Securities

Exchange Act of 1934 (Amendment No. )

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Filed by a Party other than the Registrant ☐

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☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☑ Definitive Proxy Statement

☐ Definitive Additional Materials

☐ Soliciting Material Pursuant to §240.14a-12

OTTER TAIL CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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OTTER TAIL CORPORATION

ANNUAL MEETING OF SHAREHOLDERS

Monday, April 14, 2025

10:00 A.M. (CDT)

Virtual Meeting Link: www.virtualshareholdermeeting.com/OTTR2025.

In order to be admitted to the Annual Meeting, you will need to enter the 16-Digit Control Number found on your proxy card, voting instruction form, or Notice you previously received. You may vote during the Annual Meeting by following the instructions that will be available on the virtual meeting website.

Contact Shareholder

Services for Information


E-mail			sharesvc@ottertail.com

Internet			www.ottertail.com

Phone			800-664-1259 or 218-739-8479

Mail			Otter Tail Corporation P.O. Box 496 Fergus Falls, Minnesota 56538-0496

March 3, 2025

Dear Shareholders:

We invite you to join us at our virtual 2025 Annual Meeting of Shareholders on Monday, April 14, 2025 at 10:00 A.M. (CDT). An audio archive of the Annual Meeting, including the question and answer session, will be posted on Otter Tail Corporation’s website at www.ottertail.com within a few days after the meeting’s adjournment.

Otter Tail Corporation produced record earnings in 2024, generating diluted earnings per share of $7.17. We produced a return on equity of 19 percent on an equity layer of 62 percent. In addition, 2024 marked the completion of the 86th consecutive year of paying dividends to our shareholders. Finally, in February 2025, we increased our dividend by 12 percent producing an annual indicated dividend of $2.10.

In 2024, our regulated electric utility, Otter Tail Power Company, continued to execute on its regulatory priorities. It received approval from the Minnesota Public Utilities Commission on its Integrated Resource Plan and approval from the North Dakota Public Service Commission for its general rate case. Otter Tail Power also continued to deliver on its significant rate base growth plan, investing to provide safe, reliable, efficient and increasingly clean electric service to our customers while maintaining some of the lowest electric service rates in the nation.

Our manufacturing platform faced changing market conditions throughout 2024. Our manufacturing businesses continue to navigate softened end market demand but remain well positioned to respond once demand improves. Our plastic pipe businesses produced another year of strong financial results, benefiting from customer sales volume growth and improved end market demand. We completed the first phase of Vinyltech Corporation’s expansion project, adding large diameter PVC pipe production capability, and look forward to completing our expansion project at BTD Georgia in early 2025, positioning us to better serve our customers in the southeast.

Our diversified business model continues to serve us and our stakeholders well, as our manufacturing platform generates accretive earnings, enhanced returns and positive free cash flow to fund our electric utility rate base growth plan without any equity needs. We look forward to sharing more about our 2024 operational and financial results, as well as our long-term strategy to continue to produce value for our employees, customers and shareholders during the 2025 Annual Meeting.

Your vote is important. Information concerning the matters to be considered and voted upon at the 2025 Annual Meeting along with instructions on how to vote your shares is set out in the attached Notice of 2025 Annual Meeting and Proxy Statement. Please be sure to retain your Notice or proxy card (if you received a printed copy of the proxy materials), which has your 16-Digit Control Number required to be admitted into the 2025 Annual Meeting.

Thank you for your confidence and investment in Otter Tail Corporation.




Nathan I. Partain						Charles S. MacFarlane
Chairman of the Board						President and Chief Executive Officer

Notice of Annual Meeting

NOTICE IS HEREBY GIVEN that the Annual Meeting of Shareholders of Otter Tail Corporation (the “Corporation”) will be held as a virtual meeting on Monday, April 14, 2025 at 10:00 A.M. (CDT). You can attend the Annual Meeting online, vote your shares electronically and submit your questions during the Annual Meeting, by visiting www.virtualshareholdermeeting.com/OTTR2025. You will need to have your 16‐Digit Control Number included on your Notice or your proxy card (if you received a printed copy of the proxy materials) to join the Annual Meeting. The Annual Meeting will be held to consider and act upon the following proposals:

YOUR VOTE IS IMPORTANT

Please vote your proxy by telephone or the Internet as described in the instructions

on the Notice.

If you received paper copies of the proxy materials, you could also sign, date and return the accompanying proxy card in the enclosed envelope. If your shares are held of record in a brokerage account, please follow the instructions you receive from your broker.

The Proxy Statement and Annual Report on Form 10-K were either made available to you over the Internet or mailed to you beginning on or about March 3, 2025. Shareholders who are receiving a paper copy of these materials can elect to receive future reports over the Internet by (1) visiting www.ProxyVote.com,

(2) calling 1-800-579-1639 or

(3) sending an email to sendmaterial@proxyvote.com (include your 16-Digit Control Number found on your Notice or the Proxy Card in the subject line).

To elect three Directors to Otter Tail Corporation’s Board of Directors to serve terms of three years expiring in April 2028 and until their successors are duly elected and qualified.

To approve, in a non-binding advisory vote, the compensation provided to the Named Executive Officers as described in the Proxy Statement.

To ratify the appointment of Deloitte & Touche, LLP as Otter Tail Corporation’s independent registered public accounting firm for the year 2025.

To transact such other business as may properly be brought before the meeting.

Important Notice Regarding the Internet Availability of Proxy Materials for the Shareholder Meeting to Be Held on Monday, April 14, 2025: Our Proxy Statement and Annual Report on Form 10-K are available at www.ottertail.com/annual.

March 3, 2025

JENNIFER O. SMESTAD

Vice President

General Counsel and Corporate Secretary

Table of Contents


Item			Page

Proxy Summary			1
Proxy Statement Questions and Answers			4
Proposal 1: Election of Directors			9
Board Composition and Director Qualifications			18
Corporate Governance			20
Board Leadership			21
Risk Oversight			21
Director Independence Determinations			22
Director Nomination Process			23
Meetings			23
Contact with the Board of Directors			23
Committees of the Board of Directors			23
Director Compensation			27
Annual Retainers			27
Restricted Stock Grants			27
Deferred Compensation Plan			27
Stock Ownership Guideline			27
Director Compensation Table			28
Security Ownership of Certain Beneficial Owners			29
Compensation Discussion and Analysis			31
Executive Summary			31
Purpose and Philosophy			31
Market Conditions and Peer Group			33
Elements of Executive Compensation			34
Executive Compensation Policies			43
Report of Compensation and Human Capital Management Committee			45
Executive Compensation			46
Summary Compensation Table			46
Pay Versus Performance			47

Grants of Plan-Based Awards			51
Outstanding Equity Awards at Fiscal Year-End			52
Stock Vested In Last Fiscal Year			53
Pension Benefits			53
Non-Qualified Deferred Compensation			55
Potential Payments Upon Termination or Change In Control			56
Pay Ratio Disclosure			59
Proposal 2: Advisory Vote on Executive Compensation			60
Report of Audit Committee			61
Proposal 3: Ratification of Independent Registered Public Accounting Firm			62
Pre-Approval of Audit and Non-Audit Services Policy			63
Policy and Procedures Regarding Transactions with Related Persons			64
Shareholder Proposals for 2025 Annual Meeting			65
Other Business			66

Forward-Looking Statements

The statements contained in this Proxy Statement about our future performance and operations, including, without limitation, financial and operational results, use of renewable resources and carbon emissions reductions, strategies, visions, prospects, plans, targets, goals, objectives, opportunities, consequences and all other statements that are not purely historical, are forward-looking statements for purposes of the safe harbor provisions under The Private Securities Litigation Reform Act of 1995. Although we believe that our expectations are based on information currently available and on reasonable assumptions, we can give no assurance they will be achieved. There are a number of risks and uncertainties that could cause actual results to differ materially from any forward-looking statements made herein. A discussion of some of these risks and uncertainties is contained in our Annual Report on Form 10-K and subsequent reports filed with the Securities and Exchange Commission (“SEC”), and available on our website: www.ottertail.com. In addition, any forward-looking statements included herein represent our estimates only as of the date hereof and should not be relied upon as representing our estimates as of any subsequent date. While we may elect to update forward-looking statements from time to time, we specifically disclaim any obligation to do so, even if our internal estimates change, unless otherwise required by applicable securities laws.

Proxy Summary

MEETING DETAILS

DATE

April 14, 2025

TIME

10:00 A.M. (CDT)

PLACE

www.virtualshareholdermeeting.com/OTTR2025

WAYS TO VOTE

SEC Form DEF 14A filed by Otter Tail Corporation