Objectives: People who live in unsheltered situations, such as the streets, often have poorer health, less access to health care, and an increased risk of premature mortality as compared with their sheltered counterparts. The objectives of this study were to (1) compare the characteristics of people experiencing homelessness who were sleeping primarily in unsheltered situations with those who were accessing homeless shelters and other sheltered situations, (2) identify correlates of unsheltered status, and (3) assess the relationship between unsheltered status and increased risk of mortality. Methods: Using primary data collected as part of the 100 000 Homes Campaign-a national effort to help communities find homes for vulnerable and chronically homeless Americans-we estimated 2 generalized linear mixed models to understand the correlates of unsheltered status and risk factors for mortality. Independent variables included demographic characteristics; history of homelessness, incarceration, foster care, and treatment for mental illness or substance use; sources of income; and past and present medical conditions. The study sample comprised 25 489 people experiencing homelessness who responded to an assessment of their housing and health as part of the 100 000 Homes Campaign from 2008 to 2014. Results: In the full model, the following characteristics were associated with unsheltered status: being a veteran (adjusted odds ratio [aOR] = 1.10); having 5 years), incarceration (aOR = 1.32), or substance use (aOR = 1.10 for ever abusing drugs or alcohol, aOR = 1.13 for ever using intravenous drugs, aOR = 1.98 for drinking alcohol every day for past month). Being unsheltered (aOR = 1.12), being female (aOR = 1.22), or receiving entitlements (aOR = 1.63) increased respondents’ odds of having risk factors for mortality. Conclusions: These findings highlight the need to assertively reach out to vulnerable populations and provide interventions to assist them during their transition-for example, as they exit incarceration or age out of foster care. Such a response could prevent unsheltered homelessness and thereby address increased mortality risk. Connecting people with resources to increase their access to employment, benefits, and other sources of income is especially important.