 After training with "8th U-boat Flotilla", "U-625" was transferred to "3rd U-boat Flotilla" for front-line service on 1 October 1942.She was soon transferred again, to "11th U-boat Flotilla" on 1 November 1942, then again to "13th U-boat Flotilla" on 1 June 1943, and finally to "1st U-boat Flotilla" on 1 November 1943.