UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 Title of each class Trading Symbol Name of each exchange on which registered Common Stock CARS New York Stock Exchange As of April 30, 2019, the registrant had 66,626,608 shares of common stock, $0.01 par value per share, outstanding. FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2018 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-37869 Cars.com Inc. (Exact name of Registrant as specified in its Charter) Delaware 81-3693660 (State or other jurisdiction of incorp ...