BACKGROUND: Transgender and gender diverse (TGD) individuals experience an incongruence between their assigned birth sex and gender identity. They may have a higher prevalence of health conditions associated with cancer risk than cisgender people. AIM: To examine the prevalence of several cancer risk factors among TGD individuals compared with cisgender individuals. DESIGN AND SETTING: A cross-sectional analysis was conducted using data from the UK’s Clinical Practice Research Datalink to identify TGD individuals between 1988–2020, matched to 20 cisgender men and 20 cisgender women on index date (date of diagnosis with gender incongruence), practice, and index age (age at index date). Assigned birth sex was determined from gender-affirming hormone use and procedures, and sex-specific diagnoses documented in the medical record. METHOD: The prevalence of each cancer risk factor was calculated and the prevalence ratio by gender identity was estimated using log binomial or Poisson regression models adjusted for age and year at study entry, and obesity where appropriate. RESULTS: There were 3,474 transfeminine (assigned male at birth) individuals, ,transmasculine (assigned female at birth) individuals, 131,747 cisgender men, and 13, 827 cisgender women. Transmasculine people had the highest prevalence of obesity (27.5 per cent) and ‘ever smoking’ (60.2 per cent). Transfeminine people had the highest prevalence of dyslipidaemia (15.1 per cent), diabetes (5.4 per cent), hepatitis C infection (0.7 per cent), hepatitis B infection (0.4 per cent), and HIV infection (0.8 per cent). These prevalence estimates remained elevated in the TGD populations compared with cisgender persons in the multivariable models. CONCLUSION: Multiple cancer risk factors are more prevalent among TGD individuals compared with cisgender individuals. Future research should examine how minority stress contributes to the increased prevalence of cancer risk factors in this population. [Abstract]