UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to section 13 or 15(d) of

the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 13, 2015

CarMax Auto Owner Trust 2015-2

(Issuing Entity with respect to Securities)

CARMAX BUSINESS SERVICES, LLC

(Sponsor with respect to Securities)

CARMAX AUTO FUNDING LLC

(Depositor with respect to Securities)

12800 Tuckahoe Creek Parkway, Suite 400

Richmond, VA 23238-1115

(Address of principal executive offices of registrant, including zip Code)

Registrant’s telephone number, including area code: (804) 935-4512

Former name or former address, if changed since last report: Not applicable

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

Item 1.01 and Item 8.01. Entry into a Material Definitive Agreement and Other Events

CarMax Auto Funding LLC, a Delaware limited liability company, (the “Depositor”) has registered an issuance of $14,000,000,000 aggregate principal amount of various classes of asset backed notes on Form S-3 (Commission File No. 333-189212), filed on June 10, 2013, and as amended by Pre-Effective Amendment No. 1 on June 21, 2013 (as amended, the “Registration Statement”).

On May 13, 2015 (the “Closing Date”), the Depositor entered into an Amended and Restated Trust Agreement, a copy of which is filed as an exhibit hereto, with U.S. Bank Trust National Association, as owner trustee (the “Owner Trustee”), relating to CarMax Auto Owner Trust 2015-2 (the “Issuing Entity”), a Delaware statutory trust created on August 27, 2014. On the Closing Date, CarMax Business Services, LLC (“CarMax Business Services”) and the Depositor entered into a Receivables Purchase Agreement, a copy of which is filed as an exhibit hereto, pursuant to which specified motor vehicle retail installment sale contracts and related property were sold by CarMax Business Services to the Depositor. On the Closing Date, the Issuing Entity, the Depositor and CarMax Business Services, as servicer, entered into a Sale and Servicing Agreement, a copy of which is filed as an exhibit hereto, pursuant to which motor vehicle retail installment sale contracts and related property were transferred by the Depositor to the Issuing Entity. On the Closing Date, the Issuing Entity issued to the Depositor the Class A-1 Asset-backed Notes, Class A-2a Asset-backed Notes, Class A-2b Asset-backed Notes, Class A-3 Asset-backed Notes, Class A-4 Asset-backed Notes, Class B Asset-backed Notes, Class C Asset-backed Notes and Class D Asset-backed Notes, having an aggregate original principal amount of $1,165,000,000 pursuant to an Indenture entered into between the Issuing Entity and Wells Fargo Bank, National Association, as indenture trustee (the “Indenture Trustee”), on the Closing Date, a copy of which is filed as an exhibit hereto. On the Closing Date, the Issuing Entity, the Indenture Trustee and CarMax Business Services, as administrator, entered into an Administration Agreement, a copy of which is filed as an exhibit hereto, pursuant to which the administrator agreed to perform certain duties and obligations of the Issuing Entity and the Owner Trustee under the transaction documents.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the depositor has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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