Laid down by Blohm & Voss, Hamburg on 11 March 1942, the U-boat was launched on 21 November 1942, and commissioned on 7 January 1943, by Oberleutnant zur See Franz Saar.
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-957 had a displacement of 769t when at the surface and 871t while submerged. She had a total length of 67.1m (220.1feet), a pressure hull length of 50.5m (165.7feet), a beam of 6.2m (20.3feet), a height of 9.6m (31.5feet), and a draught of 4.74m (15.55feet). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of NaNPS for use while surfaced, two Brown, Boveri & Cie GG UB 720/8 double-acting electric motors producing a total of 750PS for use while submerged. She had two shafts and two 1.23abbr=onNaNabbr=on propellers. The boat was capable of operating at depths of up to .
The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, the boat could operate for at ; when surfaced, she could travel at . U-957 was fitted with five 53.30NaN0 torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.82NaN2 SK C/35 naval gun, 220 rounds, and one twin 2sp=usNaNsp=us C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.
Under the command of Oberleutnant zur See Gerhard Schaar U-957 carried out seven war patrols between December 1943 and October 1944, sinking two commercial vessels; the British Fort Bellingham and the Soviet survey vessel Nord; and two military vessels, the American submarine chaser, and the Soviet corvette Brilliant.
Her combat career ended on 19 October 1944 at Lofoten, Norway, when she collided with a German steamer. On 21 October 1944 she was taken out of service in Trondheim.
In May 1945, she was probably scuttled in the Skjömenfjord.[1]
| Date | Ship Name | Nationality | Tonnage[2] | Fate[3] | |
|---|---|---|---|---|---|
| 26 January 1944 | Fort Bellingham |  United Kingdom | 7,153 | Sunk | |
| 26 January 1944 | USS PTC-38 | 54 | Sunk | ||
| 26 August 1944 | Nord | 411 | Sunk | ||
| 23 September 1944 | Brilliant | 550 | Sunk |