Report of Foreign Issuer Pursuant to Rule 13a-16 or 15d-16 (6-k)

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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 September, 2021

Commission File Number: 001-34848

SEANERGY MARITIME HOLDINGS CORP.

(Translation of registrant’s name into English)

154 Vouliagmenis Avenue

166 74 Glyfada

Athens, Greece

(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     ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ☐

Note: Regulation S-T Rule 101(b)(1) only permits the submission in paper of a Form 6-K if submitted solely to provide an attached annual report to security holders.

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ☐

Note: Regulation S-T Rule 101(b)(7) only permits the submission in paper of a Form 6-K if submitted to furnish a report or other document that the registrant foreign private issuer must furnish and make public under the laws of the jurisdiction in which the registrant is incorporated, domiciled or legally organized (the registrant's "home country"), or under the rules of the home country exchange on which the registrant's securities are traded, as long as the report or other document is not a press release, is not required to be and has not been distributed to the registrant's security holders, and, if discussing a material event, has already been the subject of a Form 6-K submission or other Commission filing on EDGAR.

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INFORMATION CONTAINED IN THIS REPORT ON FORM 6-K

Attached to this report on Form 6-K (this “Report”) as Exhibit 99.1 is a copy of the letter to the shareholders of Seanergy Maritime Holdings Corp. (the “Company”), the notice, proxy statement and proxy card for the Company’s 2021 Annual Meeting of Shareholders scheduled to be held on November 3, 2021.

This Report on Form 6-K is hereby incorporated by reference into the Company's Registration Statements on Form F-3 (File Nos. 333-257693, 333-253332, 333-238136, 333-237500, 333-221058, 333-166697, 333-169813 and 333-214967).

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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.

Date:  September 24, 2021

	SEANERGY MARITIME HOLDINGS CORP.
	By:	/s/ Stamatios Tsantanis
	Name:	Stamatios Tsantanis
	Title:	Chief Executive Officer

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