Icon Energy (NASDAQ: ICON) details 10.36M-share resale, $1.0M repurchase plan

Rhea-AI Filing Summary

Icon Energy Corp. has a prospectus supplement covering the potential sale from time to time of up to 10,357,237 common shares by YA II PN, Ltd. This updates an existing prospectus tied to the company’s Form F-1 registration statement.

The supplement incorporates information from a recent Form 6-K, including a commercial update and details on the company’s operations. It notes that Icon Energy’s common shares trade on the Nasdaq Capital Market under the symbol ICON, with a last reported price of $0.56 on December 17, 2025.

The board has also authorized a share repurchase program under which the company may buy back up to $1.0 million of its outstanding common shares through December 31, 2026, as described in a press release furnished with the Form 6-K.

Filed Pursuant to Rule 424(b)(3)
Registration No. 333-290206

PROSPECTUS SUPPLEMENT NO. 2

(to Prospectus dated September 22, 2025)

Icon Energy Corp.

This prospectus supplement is being filed to update, amend and supplement the information contained in the prospectus dated September 22, 2025 (as supplemented or amended from time to time, the “Prospectus”), which forms a part of our Registration Statement on Form F-1 (Registration Statement No. 333-290206), with the information contained in our report on Form 6-K filed with the Securities and Exchange Commission on December 18, 2025.

The Prospectus relates to the sale from time to time of up to 10,357,237 common shares, par value $0.001 per share (“Common Shares”) of Icon Energy Corp., incorporated under the laws of the Marshall Islands, by YA II PN, Ltd., a Cayman Islands exempt limited company.

This prospectus supplement updates, amends and supplements the information in the Prospectus and is not complete without, and may not be delivered or utilized except in combination with, the Prospectus, including any amendments or supplements thereto. This prospectus supplement should be read in conjunction with the Prospectus and if there is any inconsistency between the information in the Prospectus and this prospectus supplement, you should rely on the information in this prospectus supplement.

Our Common Shares are currently listed on The Nasdaq Capital Market under the symbol “ICON.” On December 17, 2025, the last reported sales price of our Common Shares was $0.56 per share.

Investing in our securities involves a high degree of risk. You should carefully review the risks and uncertainties described in the section titled “Risk Factors” beginning on page 6 of the Prospectus, and under similar headings in any amendments or supplements to the Prospectus.

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

The date of this prospectus supplement is December 18, 2025.

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: 001-42174

Icon Energy Corp.

(Translation of registrant’s name into English)

c/o Pavimar Shipping Co.

17th km National Road

Athens-Lamia & Foinikos Str.

14564, Nea Kifissia

Athens, Greece

+30 211 88 81 300

(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:

Form 20-F ☒ Form 40-F ☐

INFORMATION CONTAINED IN THIS FORM 6-K REPORT

On December 17, 2025, Icon Energy Corp. (the “Company”) issued a press release entitled “Icon Energy Corp. Provides Commercial Update.” A copy of this press release is furnished as Exhibit 99.1 herewith.

On December 18, 2025, the Company issued a press release announcing that the Company’s board of directors has authorized a share repurchase program under which the Company may repurchase up to an aggregate of $1.0 million of its outstanding common shares through December 31, 2026. A copy of this press release is furnished as Exhibit 99.2 herewith.

Notwithstanding the foregoing, the information in the press releases regarding the Company’s fleet and employment update, as well as its new share repurchase program is incorporated by reference into the Company’s registration statements on Form F-3 (File No. 333-291988), and shall be a part thereof, to the extent not superseded by documents or reports subsequently filed or furnished.

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.

	ICON ENERGY CORP.
Date: December 18, 2025	By:	/s/ Dennis Psachos
	Name:	Dennis Psachos
	Title:	Chief Financial Officer

FAQ

What does Icon Energy Corp. (ICON) register in this prospectus supplement?

The prospectus supplement relates to the sale from time to time of up to 10,357,237 common shares of Icon Energy Corp. by YA II PN, Ltd., updating the existing prospectus that is part of the company’s Form F-1 registration statement.

Who is selling the Icon Energy (ICON) shares covered by this prospectus?

The prospectus covers potential sales of Icon Energy’s common shares by YA II PN, Ltd., a Cayman Islands exempt limited company. The company is not identified as the seller for these shares in the described transaction.

What share repurchase program did Icon Energy (ICON) authorize?

Icon Energy’s board of directors has authorized a share repurchase program under which the company may repurchase up to an aggregate of $1.0 million of its outstanding common shares through December 31, 2026, as described in a press release furnished as Exhibit 99.2.

Which filings are updated or incorporated by reference in Icon Energy’s latest disclosure?

This prospectus supplement updates the prospectus dated September 22, 2025 that forms part of Icon Energy’s Form F-1 registration statement. It also incorporates information from a Form 6-K filed on December 18, 2025, including press releases about a commercial update and the share repurchase program.

On which exchange do Icon Energy (ICON) shares trade and what was the recent price?

Icon Energy’s common shares are listed on the Nasdaq Capital Market under the symbol ICON. The last reported sales price was $0.56 per share on December 17, 2025.

What risks does Icon Energy (ICON) highlight for investors in this context?

The company states that investing in its securities involves a high degree of risk and directs readers to the “Risk Factors” section beginning on page 6 of the prospectus, as well as similar sections in any amendments or supplements.