To assess the incidence, risk, and associated factors that contribute to an acquired surgical site infection (SSI) after emergency cesarean section (CS). This retrospective case-control study was conducted in an acute district general hospital in England with 206 patients (101 SSI patients and 105 non-SSI patients) who had an emergency CS in 2017. Grade of surgeon, smoking status, preoperative vaginal swab status (positive or negative), diabetes status, age, body mass index, membrane rupture to delivery interval, and length of surgery were recorded. Risk factors were identified using simple and multiple logistic regression. Body mass index was significantly associated with SSI (odds ratio, 1.17; 95% confidence interval, 1.11 to 1.24; P < .001). Further, substantive nonsignificant associations were recorded between SSI and patient age and vaginal swab status. Body mass index was the only significant risk factor for the development of an SSI after emergency CS, possibly because of the impact of excessive adipose tissue on the immune system and reduced effectiveness of antibiotics. Diabetes status, patient age, and preoperative vaginal swab status were not significantly associated with SSI. Improved guidelines and strategies for managing at-risk patients would enable clinicians to reduce the risk of SSI development. The importance of wound management including frequent wound cleaning, appropriate dressings, dressing changes, and education is highlighted. Future research on larger samples should be conducted to validate these findings.