INTRODUCTION AND HYPOTHESIS: The primary aim was to evaluate the impact of body mass index (BMI) category on objective and subjective cure following single incision sling (SIS) surgery for stress urinary incontinence (SUI). The secondary aim was to compare outcomes among different SIS types within and across BMI categories.METHODS: This retrospective study included 636 women (mean age 57.4 ± 10.4 years) with urodynamic SUI who underwent SIS using the Ophira, Solyx, or I-stop mini between 2015 and 2023. Patients were stratified into BMI categories: normal (