SEC Form 6-K filed by MEDIROM Healthcare Technologies Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of December, 2025

Commission File Number 001-39809

MEDIROM HEALTHCARE TECHNOLOGIES INC.

(Translation of registrant’s name into English)

2-3-1 Daiba, Minato-ku

Tokyo 135-0091, Japan

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

x Form 20-F ¨ Form 40-F

INFORMATION CONTAINED IN THIS FORM 6-K REPORT

Closing of the Sale and Issuance of Convertible Corporate Bonds

On December 12, 2025, MEDIROM Healthcare Technologies Inc. (the “Company”) closed its previously announced sale and issuance of an aggregate principal amount of JPY400,000,000 of the Company’s Third Unsecured Convertible-Type Corporate Bonds with Share Options (the “Bonds”), to 11 investors (the “Bond Holders”) under the Terms of the Third Unsecured Convertible-Type Corporate Bonds with Share Options (the “Indenture”) pursuant to the Companies Act of Japan.

The net proceeds from the sale of the Bonds are approximately JPY400,000,000. The Company intends to use the proceeds from the sale of the Bonds for general corporate or financing purposes that the Company determines to be appropriate from time to time.

The Bonds were issued and sold outside the United States in reliance upon the safe harbor provided by Regulation S promulgated under the Securities Act of 1933, as amended (the “Securities Act”). The Bonds, the common shares issuable upon the conversion of the Bonds, and any American Depositary Shares that may represent such common shares issuable upon the conversion of the Bonds have not been registered under the Securities Act, or any other securities laws, and may not be offered or sold in the United States absent registration or applicable exemption from registration requirements.

The foregoing description of the Bonds and the Indenture does not purport to be complete and is qualified in its entirety by reference to the full text of the Indenture, which is furnished herewith as Exhibit 4.1 hereto and is incorporated herein by reference.

This report on Form 6-K shall not constitute an offer to sell or the solicitation of an offer to buy the securities discussed herein, nor shall there be any offer, solicitation, or sale of the securities in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state.

Cautionary Statement Regarding Forward-Looking Statements

This report includes “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. The Company’s actual results may differ from their expectations, estimates and projections and consequently, you should not rely on these forward-looking statements as predictions of future events. Words such as “expect,” “estimate,” “project,” “budget,” “forecast,” “anticipate,” “intend,” “plan,” “may,” “will,” “could,” “should,” “believe,” “hope,” “predict,” “potential,” “continue,” and similar expressions are intended to identify such forward-looking statements. These forward-looking statements include the Company’s expectations with respect to future performance. These forward-looking statements involve significant risks and uncertainties that could cause the actual results to differ materially from the expected results. Most of these factors are outside the Company’s control and are difficult to predict. Factors that may cause such differences include but are not limited to risks and uncertainties related to the risks set forth under “Risk Factors” in the Company’s Annual Report on Form 20-F filed with the Securities and Exchange Commission (“SEC”) on April 29, 2025 and in the Company’s other filings with the SEC. The transactions described in this report on Form 6-K may not be consummated for a variety of reasons, and, even if consummated, the Company may not realize some or even all of the anticipated benefits from the transactions. In addition, if consummated, there is a risk that the transactions may have an adverse impact on the Company’s business, financial condition, and results of operations. The Company cautions readers not to place undue reliance upon any forward-looking statements, which speak only as of the date made. The Company does not undertake or accept any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements to reflect any change in its expectations or any change in events, conditions, or circumstances on which any such statement is based.

The information furnished in this report on Form 6-K (including the exhibit hereto) shall not be deemed to be “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section, and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act, as amended, except to the extent specifically provided in such a filing. The registrant hereby incorporates this report on Form 6-K (including the exhibit hereto) by reference into and as part of the Company’s registration statements on Form S-8 (Registration No. 333-274833) and Form F-3 (Registration Number 333-290161), and this report on Form 6-K shall be deemed to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished (to the extent the Company expressly states that it incorporates such furnished information by reference into such registration statement) by the Company.

EXHIBIT INDEX

+ Included as an exhibit to the Company’s report on Form 6-K filed with the SEC on December 12, 2025 and is incorporated herein by reference.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.