Mechanisms (i.e., thwarted belongingness, perceived burdensomeness, hopelessness) derived from the interpersonal theory of suicide which are hypothesized to account for the relation between sexual orientation self‐concept ambiguity and active suicide ideation were examined. Participants included 349 women, among whom 42% currently self‐ascribed a non‐exclusively heterosexual sexual identity. Among women reporting higher levels of sexual self‐concept ambiguity, greater risk for active suicide ideation is found when perceptions of burden and feelings of thwarted belonging co‐occur with feelings of hopelessness. Results support relevant theory useful for understanding suicide risk among sexual minority women who acknowledge ambiguity with regard to their sexual orientation.