Objective: To investigate Colony-Forming Unit (CFU) reduction on contaminated flexible endoscopes without a working channel after UV-C light disinfection compared to the current disinfection method with the Endoscope Washer Disinfector. Design, setting: After pharyngolaryngoscopy, a manual pre-cleaning with tap water was performed. A culture was then collected by rolling the distal 8-10 cm of the flexible endoscope over an Agar plate. The flexible endoscope was disinfected using the D60 (60-second disinfection process with UV-C light) or the Endoscope Washer Disinfector (golden standard reprocessing process with water and chemicals). Another culture was then taken. After incubation, a CFU count was performed. Results: Two hundred flexible endoscopes without a working channel were divided equally between the two disinfection groups. After clinical use and manual pre-cleaning, 84 of the 100 (84.0%) (UV-C light group) and 79 of the 100 (79.0%) (EWD) flexible endoscopes were contaminated with at least 1 CFU. Flexible endoscopes that showed no contamination after use were excluded from further analysis. After disinfection with UV-C light, 72 (85.7%) flexible endoscopes showed no contamination (i.e. 0 CFUs) versus 66 (83.5%) flexible endoscopes after reprocessing with the Endoscope Washer Disinfector. Conclusion: There is no difference in CFUs reduction on contaminated flexible endoscopes without a working channel between UV-C light disinfection and the current gold standard, the Endoscope Washer Disinfector.