ABSTRACT Objective: Lesbian, gay, and bisexual (LGB) individuals are at higher risk of poor mental health, and have more unmet mental health needs, compared to their heterosexual counterparts. Few studies have examined predictors of mental health service use amongst LGB Australians, and barriers to accessing these services Method: Participants were 592 LGB individuals (Mage = 29.39, SD = 10.83) living in urban (n= 411) and non-urban (n = 181) areas of Australia. Participants were recruited using social media advertising and completed an online questionnaire measuring mental health service use, psychological distress, and barriers to accessing services. Results: Most participants (66.6%) had accessed mental health services in the past, or had not accessed such services but reported it would have been useful (18.9%). The majority (66%) were currently experiencing psychological distress; of this group, only 18.2% had accessed services in the past one month. Barriers to accessing services included financial constraints, time limitations, and minority stress-related barriers. There was no difference between urban and non-urban respondents in their prior service use, though living in non-urban areas of Australia was associated with more barriers. Conclusions: This research highlights significant unmet mental health needs, and important barriers to accessing services, among LGB Australians Key Points What is already known about this topic: Lesbian, gay, and bisexual (LGB) people experience poorer mental health, largely due to the stigma associated with being a sexual minority in society LGB individuals have more unmet mental health needs compared to their heterosexual counterparts Those in non-urban areas of Australia have less service use and more barriers to accessing services than those in urban areas What this topic adds: Participants reported a range of barriers to accessing psychological services, including general barriers, such as service costs and distance to services, as well as minority stress-related barriers, including fears of discrimination, and a perceived lack of practitioners trained to work with LGB people Those in rural areas reported more barriers to accessing services, though there were no differences in service use between urban and non-urban participants. Women reported more service use and more barriers compared to men Barriers to accessing services were negatively associated with mental health service use, suggesting that barriers to accessing services in LGB Australians may inhibit service use