Background: To evaluate patients who underwent arthroscopic rotator cuff repair (ARCR) using a single-row technique and compare functional outcomes before and after surgery at a minimum follow-up of 3 years. Methods: This retrospective cohort study reviewed the functional outcomes of 38 patients who underwent ARCR with a single-row technique between 2015 and 2020 with a minimum follow-up of 3 years. In all procedures, the repair was medialized just lateral to the articular cartilage with bone tunneling on the footprint (crimson duvet). Functional outcomes were evaluated from the visual analog scale score, muscle strength, range of motion, Constant-Murley Score, and American Shoulder and Elbow Surgeons score, which were compared before and after surgery. Results: All cases had medium and large supraspinatus tears with a median age of 60 years (40-77 years). As much as 68% of tears were in the dominant hand, and most of the cases (79%) were of nontraumatic origin. Additional procedures such as acromioplasty (26%), biceps tenodesis (8%), and biceps tenotomy (18%) were done in addition to tendon repair. Women were dominant in all cases (58%). There was a significant improvement in the median visual analog scale score (8-1), muscle power, and range of motion when comparing the results before and after ARCR. Functional American Shoulder and Elbow Surgeons score and Constant-Murley Score also significantly improved from 50 to 91 and 46 to 85, respectively (P < .05). Conclusion: ARCR with a single-row technique provides good results for medium and large tears in 3 years of follow-up. © 2025 The Author(s)