Objective Our aim was to conduct an up-to-date systematic review of randomised controlled trials (RCTs) to determine the benefits and harms of enhanced recovery after surgery (ERAS) programme in bariatric surgery. Methods MEDLINE, Embase, PubMed, CINAHL and the Cochrane Library were searched for RCTs on ERAS versus standard care (SC) until April 2020. The primary endpoint was the length of hospital stay (LOS). Results Five RCTs included a total of 610 procedures. ERAS adoption is capable of significantly reducing LOS (MD of − 0.51; 95% CI − 0.92 to − 0.10; P  = 0.01) and postoperative nausea and vomiting (PONV) (OR 0.42; 95% CI 0.19 to 0.95; P  = 0.04). No significant differences in terms of adverse events and readmissions. Conclusions The implementation of ERAS in bariatric surgery produces a significant reduction in LOS and PONV.