Sex practices among heterosexuals are not well studied. We aimed to explore sexual practices among heterosexuals attending a sexual health clinic. This cross-sectional survey was conducted at Melbourne Sexual Health Centre between March and April 2019. Data were collected on kissing, oral sex (fellatio or cunnilingus), vaginal sex, anal sex and rimming in the previous 3 months. Univariable and multivariable logistic regression analyses were performed to examine the associations between engaging in anal sex and other sex practices. There were 709 participants (333 men; 376 women) who were eligible and completed the survey (response rate was 24.6%). In the past 3 months, most participants had had vaginal sex (n = 677; 95.5%), with a mean of 3.0 (standard deviation (SD): 3.9) vaginal sex partners, and half reported engaging in condomless vaginal sex in the past 3 months (n = 358; 50.1%). A total of 135 (19.0%) participants had had anal sex, with a mean of 1.3 (SD: 1.0) anal sex partners, with 63.5% (n = 94) engaging in any condomless anal sex in the past 3 months. Most participants (n = 637, 89.8%) had received oral sex in the past 3 months; this proportion did not differ by age group or gender. Women (n = 351, 93.4%) were more likely to perform oral sex than men (n = 275; 82.6% men) (p < 0.001) and to have received rimming (26.6% women vs. 12.6% men; p < 0.001). Men were more likely to have performed rimming (25.5% men vs. 9.3% women; p < 0.001). After adjusting for age, number of partners and sexual practice, anal sex was associated with being ≥35 years (adjusted odds ratio (aOR): 2.3; 95% CI: 1.2–4.2), receiving rimming (aOR: 3.8; 95% CI: 2.4–6.0) and performing rimming (aOR: 2.8; 95% CI: 1.8–4.6). Rimming and anal sex are practiced by one-fifth or more of heterosexuals. Older heterosexuals were more likely to engage in anal sex and to perform rimming. Future research should consider the benefits of testing extragenital sites where appropriate.