Lesbian, gay, and bisexual (LGB) individuals have elevated rates of substance use disorders and present to treatment with more severe substance use problems. Despite this health disparity, recent reviews highlight the paucity of studies reporting sexual orientation in substance use research (e.g., Flentje, Bacca, & Cochran, 2015). Using data from 5 clinical trials of contingency management (CM), the current study investigated the impact of sexual orientation on 3 substance use outcomes: treatment retention, longest duration of abstinence, and percent negative samples submitted. Participants (N = 912; mean age = 36.6 years; 51.1% female; 45% African American, 42.2% Caucasian) were randomized to standard care in community-based intensive outpatient treatment (IOP) or the same plus CM. Patients identifying as LGB made up 10.6% of the sample. A significant proportion identified as bisexual (8.2% of the total sample). Regardless of sexual orientation, participants receiving CM achieved better treatment outcomes than those receiving IOP alone. There were no statistically significant differences between LGB and heterosexual participants in their response to IOP in general, and CM specifically, across all 3 treatment outcomes (ps < .05). However, equivalence testing revealed that outcomes were not statistically equivalent for LGB and heterosexual participants, with the exception of percentage of negative samples, which was equivalent within the CM group only. Differences in treatment response to CM and standard community-based IOP do not reach the level of statistical significance; however, in most cases, we cannot conclude that treatment response is equivalent for LGB and heterosexual individuals.