UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF

THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): November 28, 2025

CAPSTONE HOLDING CORP.

(Exact name of registrant as specified in its charter)

5141 W. 122nd Street

Alsip, IL 60803

(Address of principal executive offices)

Registrant’s telephone number, including area code: (708) 371-0660

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 1.01. Entry into a Material Definitive Agreement.

As previously disclosed, on July 29, 2025, Capstone Holding Corp. (the “Company”) entered into a securities purchase agreement (the “Purchase Agreement”) with an institutional investor (the “Buyer”), pursuant to which the Company authorized the issuance of senior secured convertible notes to the Buyer, in the aggregate original principal amount of up to $10,909,885, which are being issued with a 8.34% original issue discount (each, a “Convertible Note”). The first Convertible Note was issued in the original principal amount of approximately $3,272,966 (the “July 2025 Convertible Note”), and the second Convertible Note was issued in the original principal amount of approximately $3,545,712.42 (the “October 2025 Convertible Note”, and together with the July 2025 Convertible Note, the “Notes”). The Convertible Notes are convertible into shares of common stock, $0.0005 par value per share (the “Common Stock”) in certain circumstances in accordance with the terms of the Convertible Notes, with the July 2025 Convertible Note having an initial conversion price per share of $1.72 (subsequently reduced to $1.00) and the October 2025 Convertible Note having a conversion price of $1.10 (the “Conversion Price)”.

Pursuant to the effective registration statements on Form S-1 (File Nos. 333-289222 and 333-291041), the Company registered a total of 8,388,336 shares of Common Stock issuable upon conversion of the Convertible Notes.

On November 28, 2025, pursuant to Section 7(h) of the Notes, the Company and the Buyer agreed, pursuant to a Conversion Price Voluntary Adjustment Notice signed by both parties, to reduce the Conversion Price to $0.75 with regard to the entire amount of the July 2025 Convertible Note still owed in the principal amount $500,744.01, and with regard to $1,772,856.21 of the principal amount of the October 2025 Convertible Note (with $1,772,856.21 of the principal balance of the October 2025 Convertible Note still having a $1.10 conversion price).

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

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 hereunto duly authorized.

2