Previous studies indicate that homosexual or bisexual individuals are at a higher risk of attempting suicide compared to heterosexuals. To overcome biases in these studies, more rigorous definitions of "suicide attempts" and the assessment of multiple dimensions of sexual orientation are needed. In addition, studies from the German speaking region are sparse, especially those not recruiting participants from the gay or lesbian communities. We solicited self-reported suicide attempts among 1,382 Austrian adults recruited through structured snowball sampling from students' social networks. Suicide attempts were more frequently reported by those participants with homosexual or bisexual fantasies, partner preference, behavior, and self-identification, compared to their heterosexually classified counterparts. This was true for any dimension of sexual orientation and for suicide attempts with intent to die or suicide attempts that required medical treatment. Our Austrian study confirmed existing evidence that homosexual and bisexual individuals are at an increased risk for attempting suicide. This should be considered in suicide preventive efforts.