People experiencing homelessness have significantly lower life expectancies than the general population, and among those aged ≥ 45, tobacco-related illnesses are the leading cause of death.[1] Compared to the general population, tobacco use among people experiencing homelessness is six times higher, and the quit ratio (ratio of former to ever-smokers) is five times lower. [2],[3] We used the largest representative study of people experiencing homelessness since the 1990s to estimate tobacco use prevalence and its association with shelter status, behavioral health, and health services use among adults experiencing homelessness in California to identify opportunities to address unmet tobacco treatment needs.