Transurethral radiofrequency collagen denaturation, a nonsurgical treatment for stress urinary incontinence, reduces regional dynamic tissue compliance without causing tissue necrosis or gross tissue shrinkage, unlike transvaginal radiofrequency tissue ablation. This retrospective study evaluated long-term safety and efficacy in 21 patients from a 12-month, randomized controlled trial utilizing 3-day diaries and the Incontinence Quality of Life (I-QOL) survey. Significant increases in overall I-QOL scores 3 years or more post treatment was the primary end point. Secondary end points were reductions in frequency and severity of incontinence episodes. After 3 years, mean overall I-QOL score improvement was 12.7 (+/-26); 56% of patients achieved 50% or more reduction in frequency. No new adverse events occurred. These results indicate that radiofrequency collagen denaturation is safe and provides durable efficacy.