UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-A

FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES

PURSUANT TO SECTION 12(b) OR 12(g) OF

THE SECURITIES EXCHANGE ACT OF 1934

Redwood Mortgage Investors IX, LLC

(Exact name of registrant as specified in its charter)

1825 S. Grant Street, Suite 250

San Mateo, CA 94402-2678

(Address and zip code of principal executive offices)

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

If this form relates to the registration of a class of securities pursuant to Section 12(b) of the Exchange Act and is effective pursuant to General Instruction A.(c) or (e), check the following box.  ¨

If this form relates to the registration of a class of securities pursuant to Section 12(g) of the Exchange Act and is effective pursuant to General Instruction A.(d) or (e), check the following box.  x

If this form relates to the registration of a class of securities concurrently with a Regulation A offering, check the following box.  ¨

Securities Act registration statement or Regulation A offering statement file number to which this form relates:  Not applicable

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

Redwood Mortgage Investors IX, LLC (the “Company”) is incorporating by reference herein the description of its units of limited liability company interests (the “Units”) set forth under the captions “Description of Units” and “Transfer of Units – Unit Redemption Program” in the Company’s Registration Statement on Form S-11 (File No. 333-208315) filed with the U.S. Securities and Exchange Commission (the “Commission”) on December 2, 2015, as amended (the “Registration Statement”), and in the prospectus included in the Registration Statement to be filed separately by the Company with the Commission pursuant to Rule 424(b) under the Securities Act of 1933, as amended (the “Prospectus”).

The Company is also incorporating by reference herein additional information set forth under the caption “Summary of Ninth Amended and Restated Limited Liability Company Operating Agreement” in the Prospectus. The Registration Statement registers the offer and sale of up to $140,000,000 of Units as part of a continuous offering of Units which began in 2009.

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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, thereto duly authorized.

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Exhibit Index