SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-A

FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
PURSUANT TO SECTION 12(B) OR (G) OF THE
SECURITIES EXCHANGE ACT OF 1934

Aclaris Therapeutics, Inc.

(Exact Name of Registrant as Specified in its Charter)

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

Securities Act registration statement number to which the form relates:  333-206437

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

None

Item 1.                                                         Description of Registrant’s Securities to be Registered.

Aclaris Therapeutics, Inc. (the “Registrant”) hereby incorporates by reference the description of its common stock, par value $0.00001 per share, to be registered hereunder contained under the heading “Description of Capital Stock” in the Registrant’s Registration Statement on Form S-1 (File No. 333-206437), as originally filed with the Securities and Exchange Commission (the “Commission”) on August 17, 2015, as subsequently amended on September 4, 2015, September 25, 2015 and October 1, 2015 (the “Registration Statement”), and in the prospectus included in the Registration Statement to be filed separately by the Registrant with the Commission pursuant to Rule 424(b) under the Securities Act of 1933, which description included in such prospectus shall be deemed to be incorporated by reference herein.

Item 2.                                                         Exhibits.

Pursuant to the Instructions as to Exhibits with respect to Form 8-A, no exhibits are required to be filed because no other securities of the Registrant are registered on The NASDAQ Stock Market LLC and the securities registered hereby are not being registered pursuant to Section 12(g) of the Securities Exchange Act of 1934, as amended.

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SIGNATURE

Pursuant to the requirements of Section 12 of the Securities Exchange Act of 1934, the Registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized.

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