This paper reports two studies that tested sexual orientation, residence context (urban/rural, living with parents), and perceived social support as predictors of sexual orientation disclosure in lesbian, gay, bisexual, and other sexual minority (LGB+) university students in Chile. Samples comprised 268 participants for Study 1, and 160 for Study 2, who were cisgender, transgender, or nonbinary. All participants answered an online questionnaire with sociodemographic questions, a perceived social support scale, and a list of individuals to whom they disclosed their sexual orientation. In both studies, the predictors of sexual orientation disclosure were being gay or lesbian (vs. bisexual and other sexual minority individuals), not living with parents, and perceiving social support from others outside family and friends. Our findings show the need to expand the social understanding of sexual orientation beyond heterosexual-homosexual dichotomies, and to strengthen sources of social support in higher education to foster safer environments for sexual and gender minority students.