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): October 8, 2015 (October 2, 2015)

OPTIMUMBANK HOLDINGS, INC.

(Exact name of registrant as specified in charter)

2477 East Commercial Boulevard, Fort Lauderdale, FL 33308

(Address of Principal Executive Offices) (Zip Code)

(954) 900-2800

(Registrant’s telephone number, including area code)

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 (see General Instruction A.2. below):

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 3.01 Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing.

On April 2, 2015, the staff of The Nasdaq Stock Market (“Nasdaq”) notified OptimumBank Holdings, Inc. (the “Company”) that the bid price of its common stock had closed at less than $1 per share over the previous 30 consecutive business days, and, as a result, did not comply with Nasdaq Listing Rule 5550(a)(2) (the “Rule”). In accordance with Listing Rule 5810(c)(3)(A), the Company was provided 180 calendar days, or until September 29, 2015, to regain compliance with the Rule.

On October 2, 2015, the Company received a letter from the staff at Nasdaq notifying the Company that it had not regained compliance with the Rule and was not eligible for a second 180 day period. Specifically, Nasdaq further informed the Company that it was not able to comply with the stockholders’ equity initial listing requirement for The Nasdaq Capital Market.

Based on the foregoing, unless the Company requests an appeal of Nasdaq’s determination, the Company’s common stock will be scheduled for delisting from The Nasdaq Capital Market.

The Company plans to appeal Nasdaq’s determination. The Company plans to regain compliance with the Nasdaq listing requirements by effecting a reverse stock split.

The Company’s appeal will stay the delisting of the Company’s common stock.

There can be no assurance that the Company’s appeal will be successful, that any plan to be submitted by the Company will be accepted, or that the Company will be able to regain or maintain compliance with the requirements for continued listing under the Nasdaq Listing Rules. There can be no assurance that the Company will maintain its Nasdaq listing.

This Current Report on Form 8-K contains forward-looking statements as that term is defined in the federal securities laws. The events described in forward-looking statements contained in this Current Report on Form 8-K may not occur. Generally these statements relate to business plans or strategies, projected or anticipated benefits or other consequences of the Company’s plans or strategies, financing plans, projected or anticipated benefits from acquisitions that the Company may make, or projections involving anticipated revenues, earnings or other aspects of the Company’s operating results or financial position, and the outcome of any contingencies. Any such forward-looking statements are based on current expectations, estimates and projections of management. The Company intends for these forward-looking statements to be covered by the safe-harbor provisions for forward-looking statements. Words such as “may,” “will,” “expect,” “believe,” “anticipate,” “project,” “plan,” “intend,” “estimate,” and “continue,” and their opposites and similar expressions are intended to identify forward-looking statements. The Company cautions you that these statements are not guarantees of future performance or events and are subject to a number of uncertainties, risks and other influences, many of which are beyond the Company’s control, that may influence the accuracy of the statements and the projections upon which the statements are based. All cautionary statements made in this Current Report on Form 8-K should be read as being applicable to all related forward-looking statements wherever they appear.

SIGNATURE

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.