Following release from prison, housing and health issues form a complex and mutually reinforcing dynamic, increasing reincarceration risk. Supported accommodation aims to mitigate these post-release challenges. We describe the impact of attending Rainbow Lodge (RL), a post-release supported accommodation service for men in Sydney, Australia, on criminal justice and emergency health outcomes. Our retrospective cohort study using linked administrative data includes 415 individuals referred to RL between January 2015 and October 2020. Outcomes of interest were rates of criminal charges, emergency department (ED) presentations and ambulance attendance; and time to first reincarceration, criminal charge, ED presentation and ambulance attendance. The exposure of interest was attending RL; covariates included demographic characteristics, release year and prior criminal justice and emergency health contact. Those who attended RL (n = 170, 41%) more commonly identified as Aboriginal or Torres Strait Islander (52% vs 41%; p = 0.025). There was strong evidence that attending RL reduced the incidence criminal charges (adjusted rate ratio [ARR] = 0.56; 95% confidence interval [CI] 0.340.86; p = 0.009). Absolute rates indicate a weak protective effect of RL attendance on ED presentation and ambulance attendance; however, adjusted analyses indicated no evidence of an association between attending RL and rates of ED presentations (ARR = 0.88; 95% CI = 0.65–1.21), or ambulance attendance (ARR = 0.82; 95% CI = 0.57–1.18). There was no evidence of an association between attending RL and time to first reincarceration, charge, ED presentation or ambulance attendance. Greater detail about reasons for emergency health service contact and other self-report outcome measures may better inform how supported accommodation is meeting its intended aims.