In the aftermath of Russia's military response to the 2014 Revolution of Dignity, the government of Ukraine implemented a package of health financing reforms underpinned by universal health coverage (UHC) principles. By the time of Russia's full-scale invasion of Ukraine in February 2022, the new systems and institutions envisaged in the reforms were largely established. In this Commentary article, we explain how these attributes strengthened the Ukrainian health system's response to the impacts of the war. Ukraine's experience highlights the role that health financing arrangements, designed in accordance with UHC principles, can play in strengthening health system resilience.