Aim <p>This study assesses sex-specific trends in diabetes prevalence and associated risk factors in the Swiss population between 2002 and 2022.</p> Subject and methods <p>We conducted a repeated cross-sectional analysis using data from the Swiss Health Surveys in 2002 (<i>n</i> = 18,654) and 2022 (<i>n</i> = 21,903), which is representative of the Swiss population. Participants’ diabetes status, body mass index (BMI), physical activity, education, lifestyle behaviors, and cardiometabolic risk factors were assessed and quantified using sex-stratified logistic regressions, and Oaxaca-Blinder decomposition.</p> Results <p>Diabetes prevalence increased from 4.4% in 2002 to 6.4% in 2022 (men 4.8% to 7.4%; women 4.1% to 5.5%). Obesity (BMI ≥ 30&#xa0;kg/m²) became more common among individuals with diabetes (men 20.8% to 31.6%; women 22.7% to 26.0%) and was the factor most strongly associated with diabetes with BMI 18.5–24.9&#xa0;kg/m² as a reference, with an odds ratio (OR) of 2.74 (95% CI [2.43–3.09]) in men and 2.91 (95% CI [2.60–3.27]) in women. Combined BMI ≥ 30&#xa0;kg/m² and physically active conferred higher risk with an OR of 5.05 (95% CI [4.66–5.46]) than BMI 18.5–24.9&#xa0;kg/m² and physically inactive with 2.09 (95% CI [1.89–2.30]). The Oaxaca-Blinder decomposition showed that sex differences in diabetes risk were predominantly explained by age and lifestyle factors differences in 2002, and by differential effects of these factors in 2022.</p> Conclusion <p>Diabetes prevalence rose in Switzerland between 2002 and 2022, with BMI remaining the dominant modifiable risk factor, followed by physical activity. Prevention strategies should prioritize weight management, while promoting healthy lifestyle behaviors across all groups.</p>