X0508 4 2025-11-17 0 0001438133 TANDEM DIABETES CARE INC TNDM 0001804186 Kyrillos Jean-Claude 12400 HIGH BLUFF DRIVE SAN DIEGO CA 92130 0 1 0 0 EVP & Chief Operating Officer 0 Common Stock 2025-11-17 4 A 0 160 15.59 A 22544 D The reporting person is voluntarily reporting the acquisition of shares of common stock pursuant to the Tandem Diabetes Care Inc. Amended and Restated 2013 Employee Stock Purchase Plan (ESPP), for the ESPP purchase period of May 16, 2025, through November 17, 2025. This transaction is also exempt under Rule 16b-3(c). /s/ Shannon M. Hansen, Attorney-in-Fact for Jean-Claude Kyrillos 2025-11-19