The study aimed to estimate the global prevalence and incidence of urogenital infections with chlamydia, gonorrhoea, trichomoniasis, and syphilis in women and men aged 15–49 years in 2016. For chlamydia, gonorrhoea, and trichomoniasis, systematic reviews were conducted to identify studies reporting prevalence from 2009 to 2016, with additional input from regional experts. Bayesian meta-analysis was used to generate estimates. For syphilis, national estimates generated using Spectrum-STI were aggregated. The estimated global prevalence of chlamydia in women was 3.8% (95% UI: 3.3–4.5), gonorrhoea 0.9% (95% UI: 0.7–1.1), trichomoniasis 5.3% (95% UI: 4.0–7.2), and syphilis 0.5% (95% UI: 0.4–0.6). In men, the prevalence estimates were 2.7% (95% UI: 1.9–3.7) for chlamydia, 0.7% (95% UI: 0.5–1.1) for gonorrhoea, 0.6% (95% UI: 0.4–0.9) for trichomoniasis, and 0.5% (95% UI: 0.4–0.6) for syphilis. The total estimated incident cases were 376.4 million, with 127.2 million chlamydia cases, 86.9 million gonorrhoea cases, 156.0 million trichomoniasis cases, and 6.3 million syphilis cases. The study highlights the need for expanded data collection efforts at the country level and provides a baseline for monitoring progress towards the World Health Organization's global health sector strategy on sexually transmitted infections (STIs) for 2016–2021.The study aimed to estimate the global prevalence and incidence of urogenital infections with chlamydia, gonorrhoea, trichomoniasis, and syphilis in women and men aged 15–49 years in 2016. For chlamydia, gonorrhoea, and trichomoniasis, systematic reviews were conducted to identify studies reporting prevalence from 2009 to 2016, with additional input from regional experts. Bayesian meta-analysis was used to generate estimates. For syphilis, national estimates generated using Spectrum-STI were aggregated. The estimated global prevalence of chlamydia in women was 3.8% (95% UI: 3.3–4.5), gonorrhoea 0.9% (95% UI: 0.7–1.1), trichomoniasis 5.3% (95% UI: 4.0–7.2), and syphilis 0.5% (95% UI: 0.4–0.6). In men, the prevalence estimates were 2.7% (95% UI: 1.9–3.7) for chlamydia, 0.7% (95% UI: 0.5–1.1) for gonorrhoea, 0.6% (95% UI: 0.4–0.9) for trichomoniasis, and 0.5% (95% UI: 0.4–0.6) for syphilis. The total estimated incident cases were 376.4 million, with 127.2 million chlamydia cases, 86.9 million gonorrhoea cases, 156.0 million trichomoniasis cases, and 6.3 million syphilis cases. The study highlights the need for expanded data collection efforts at the country level and provides a baseline for monitoring progress towards the World Health Organization's global health sector strategy on sexually transmitted infections (STIs) for 2016–2021.