SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 F O R M 6-K REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE SECURITIES EXCHANGE ACT OF 1934 For the month of May 2021 MER TELEMANAGEMENT SOLUTIONS LTD. (Name of Registrant) 15 Hatidhar Street, Ra'anana 43665, Israel (Address of Principal Executive Office) Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40- Form 20-F ☒ Form 40-F ☐ Indicate by check mark if th ...

SECURITIES AND EXCHANGE COMMISSION Washington D.C. 20549 FORM 20-F ☐ REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from __________ to __________ ☐ SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SE ...