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As filed with the Securities and Exchange Commission on February 13, 2018

Registration No. 333-222517

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

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AMENDMENT NO. 3
TO
FORM S-1
REGISTRATION STATEMENT
Under
The Securities Act of 1933

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AVINGER, INC.
(Exact name of Registrant as specified in its charter)

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400 Chesapeake Drive
Redwood City, California 94063
(650) 241-7900
(Address, including zip code, and telephone number, including area code, of Registrant's principal executive offices)

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Jeffrey M. Soinski
Chief Executive Officer
Avinger, Inc.
400 Chesapeake Drive
Redwood City, CA 94063
(650) 241-7900
(Name, address, including zip code, and telephone number, including area code, of agent for service)

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Copies to:
Philip H. Oettinger
Wilson Sonsini Goodrich & Rosati
Professional Corporation
650 Page Mill Road
Palo Alto, California 94304
(650) 493-9300

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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, check the following box. ý

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

         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. o

         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. o

         Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

         If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.    ý

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         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.

   

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EXPLANATORY NOTE

        This Amendment No. 3 (the "Amendment") to the Registration Statement on Form S-1 (File No. 333-222517) (the "Registration Statement") of Avinger, Inc. is being filed solely for the purpose of filing certain exhibits to the Registration Statement and updating Item 16 of Part II of the Registration Statement. Accordingly, the Amendment consists solely of the facing page, this explanatory note, Item 16 of Part II of the Registration Statement, the index to exhibits, the signatures and the filed exhibits and is not intended to amend or delete any part of the Registration Statement except as specifically noted herein.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 16.    Exhibits and Financial Statement Schedules

        The following exhibits are filed as part of this registration statement.

II-1

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II-2

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II-3

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SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the registrant has duly caused this amendment to registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Redwood City, State of California, on the 13^th day of February, 2018.

        Pursuant to the requirements of the Securities Act of 1933, this amendment to registration statement has been signed by the following persons in the capacities and on the dates indicated:

II-4

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EXPLANATORY NOTE
PART II INFORMATION NOT REQUIRED IN PROSPECTUS

Item 16. Exhibits and Financial Statement Schedules