Abstract It’s well documented that obesity is a positive predictor of surgical morbidity and with increasing obesity rates it is becoming a challenge for patients presenting with obesity related surgical conditions such as acute cholecystitis. This study aims to assess the impact of the class of obesity on the outcomes following laparoscopic cholecystectomy for acute cholecystitis. Methods A retrospective observational study was performed on patients undergoing emergency laparoscopic cholecystectomy at UHNM from January 2022 to January 2023. These patients were then stratified by their class of obesity as defined by the WHO; Healthy weight (BMI <25), Overweight (BMI 25 – 30), ClassI Obesity (BMI 30-35), ClassII Obesity (BMI 35-40), and ClassIII Obesity (BMI >40). Primary outcomes included LOS, mortality, 30 day readmission rates and postoperative complications. Secondary outcomes included total operative time. Results A total of 643 patients were identified. The classes of obesity were on average a younger cohort (median age, Healthy Weight = 60 [32–82], Overweight = 62 (28-86), Class I = 56 (27-80) ClassII = 50 (22-83) and ClassIII = 47 (28-90); p < 0.001). Length of hospital stay, mortality and operative duration, were similar between groups. However readmission rates were higher for the obese groups (Healthy Weight 8% vs Overweight 8% vs ClassI = 7% vs ClassII = 14% vs ClassIII 16%; p < 0.001) and postoperative complications (p = 0.067). Conclusions Emergency laparoscopic cholecystectomy can be performed safely on patients with higher classes of obesity but an appreciation of the class of obesity needs to be taken into consideration and higher class of obesity is associated with increasing risk of post operative complications.