As filed with the Securities and Exchange Commission on December 29, 2011.

Registration No. 333-178049

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

AMENDMENT NO. 2

TO

Form S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

SYNACOR, INC.

(Exact Name of Registrant as Specified in its Charter)

40 La Riviere Drive, Suite 300

Buffalo, NY 14202

(716) 853-1362

(Address, including zip code and telephone number, including area code, of registrant’s principal executive offices)

Ronald N. Frankel

President and Chief Executive Officer

Synacor, Inc.

40 La Riviere Drive, Suite 300

Buffalo, NY 14202

(716) 853-1362

(Name, address, including zip code and telephone number, including area code, of agent for service)

Copies to:

Approximate date of commencement of proposed sale to the public: As soon as practicable after the effective date of this Registration Statement.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, as amended, check the following box.  ¨

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of earlier effective registration statement for the same offering.  ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definitions of “large accelerated filer,” “accelerated filer,” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

CALCULATION OF REGISTRATION FEE

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, or until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

EXPLANATORY NOTE

This Amendment No. 2 to the Registration Statement on Form S-1 (File No. 333-178049) is solely made to file exhibits previously omitted. No changes have been made to Part I of the Registration Statement or Items 13, 14, 15, 16(b) or 17 of Part II of the Registration Statement. Accordingly, this amendment consists only of the facing page, this explanatory note, Item 16(a) of Part II of the Registration Statement, the signature page to the Registration Statement and the filed exhibits.

(a) Exhibits

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II-2

Notes:

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this amendment no. 2 to the registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Buffalo, State of New York, on this 29^th day of December, 2011.

Pursuant to the requirements of the Securities Act, this amendment no. 2 to the registration statement has been signed by the following persons on behalf of the registrant and in the capacities and on the dates indicated:

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INDEX TO EXHIBITS

Notes: