Background The 7,100,000 people released from US jails each year have high suicide risk, but their proportion of all suicides is unknown.

Objective Assess what proportion of US adults who died by suicide spent at least one night in jail during the year and two years preceding death. If appropriate, envision community suicide prevention targeting this population.

Methods Cohort study of people with US jail exposure: daily census, release, and suicide counts/rates during incarceration from published/online data. We multiplied the number of people released times six estimates of suicide death rates post-release drawn from nine single studies or ones we meta-analytically grouped. We estimated the decreasing death rate over time post-release using data from seven studies. Three were from North America. Six included unconvicted populations awaiting arraignment or trial. Five let us decompose rates by sex. Estimate check: US data on deaths while incarcerated times the mean ratio across seven studies of (deaths post-release/deaths while incarcerated). For comparison: estimated suicide death rates for people who were not recently incarcerated and people with prison exposure.

Results In 2019, 2.8% of the US adult population were released from jail at least once, typically after brief pre-trial stays. Relative to US adults not incarcerated during the year, risk of suicide death ranged from 7.4 to 11.3 in the year after jail release into the community and 6.6 across the two years post-release. People within two years after release from jail accounted for 27.6%-34.7% of all US adult suicide deaths, including 16.7%-23.8% within one year after release (24.2% for women, 23.7% for men). The ratio method yielded a broader 16.5%-28.4% range within one year. People in jail accounted for 0.8% of adult suicide deaths, people in or released from prison another 2.2%-2.8%.

Conclusions Suicide prevention efforts focused on return to the community after jail would reach one fourth to one third of US adults within two years before they would otherwise die by suicide. To reduce the US suicide rate, health systems should develop infrastructure to identify these high-risk returnees and partner with community-based providers to coordinate suicide prevention targeting them.