BACKGROUND: Childhood sexual abuse (CSA) and homelessness are major public health problems with elevated prevalence among people diagnosed with bipolar disorder (BD). While CSA is a known risk factor for homelessness, little research has examined sex differences in the relationship between CSA and adult homelessness among people with BD. METHODS: This study tested whether sex moderates the CSA-homelessness relationship such that greater CSA severity predicts higher risk of adult homelessness for females but not males. Data were collected from 201 outpatients at a bipolar outpatient clinic in the Southeastern U.S., most of whom identified as female and Black/African American and reported low income. Self-report data were collected at one clinic visit and analyzed using moderated logistic regression. RESULTS: CSA was reported by 76.3 % of females and 43.5 % of males. Sex moderated the CSA-homelessness relationship (p <
.01). CSA severity was significantly associated with adult homelessness for females (OR = 1.08, 95 % CI: [1.02, 1.15]) but not for males. LIMITATIONS: Internal and external validity were constrained by the non-representative sample, self-report biases, and a cross-sectional design. CONCLUSIONS: Findings highlight sex differences in the long-term consequences of CSA among underserved populations with BD, identifying CSA as a significant predictor of adult homelessness for females. Further research should explore bipolar symptomatology, sociocultural factors, and other potential mediators. Results underscore the need for integrated mental health and social services that are accessible across the lifespan, sex- and gender-sensitive, and trauma-informed.