Purpose There are only a small number of studies providing a comparison between SADI-S and Hess-Marceau's BPD/Duodenal Switch (RY-DS) operations. We aimed to compare 5-year results of SADI-S 250 (common limb 250 cm) with RY-DS. Material and Methods Data of patients who underwent open SADI-S (n226) and RY-DS (n528) were retrospectively studied. EWL(%), EBMIL(%), TWL(%), antidiabetic effect, complications, and revision rate were compared between the two groups. Results After the first 12 months, EWL% (77.0% vs 73.3%) and TWL% (39.4% vs 38.9%) were statistically significantly better after SADI-S (p < 0.01, andp < 0.05 respectively), but not EBMIL% (p > 0.05). At nadir to 24-36 months, EWL, TBWL, and EBMIL after SADI-S was comparable to the RY-DS group. Up to the fourth and fifth year, better weight loss (TBWL, EBMIL, EWL) was observed after RY-DS than after SADI-S. Early complication rate was less (2.65%) in the SADI-S group vs 5.1% in the RY-DS. Protein deficiency and small bowel obstruction rates were also lower after SADI-S. 93.4% of patients achieved total remission of their diabetes. 7.5% of patients in the SADI-S group had symptoms of bile reflux, which was a main indication for revisions. Conclusion SADI-S has many advantages over RY-DS. However, weight loss and antidiabetic effects after the third year were marginally lower after SADI-S compared to RY-DS. SADI-S is less dangerous in terms of malabsorption and looks to be a reasonable alternative to RY-DS as a metabolic operation. RY-DS could be implemented for weight regain and/or bile reflux after SADI-S.