For the transition period from to Commission file number 001-14157 TELEPHONE AND DATA SYSTEMS, INC. (Exact name of Registrant as specified in its charter) (State or other jurisdiction of incorporation or organization) (IRS Employer Identification No.) 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, 2019 OR ☐ TRANSITION REPORT PURSUANT TO S ...