Objective: To evaluate stent patency with and without endoscopic sphincterotomy in malignant biliary obstruction. Methods: This prospective study was conducted in Endoscopy Suite, Surgical Unit IV, Civil Hospital Karachi from April, 2021 to January, 2022 for a period of 10 months. Patients undergoing ERCP for inoperable malignant biliary obstruction were randomized into EST group and non EST group. Stent patency was the primary end point. Patients were evaluated for resolution of jaundice, bleeding, perforation, pancreatitis and cholangitis. Statistical analysis was performed using the SPSS version 22. Results: Total number of patients was 83. Out of which 48 patients were in EST group and 35 in non EST group. 55 pts were male and 28 were female with a mean age of 64.2 ± 7.2 yrs. Stent patency was higher in non EST group (74.28% vs 68% P < 0.05). There was no significant difference in other complications between the two groups. Conclusion: In our study stent patency was significantly higher in non EST group.