| Date | Operator | Ship | Class and type | Notes |
|---|
| March 2 | Royal Navy | Avenger (D14) | Avenger-class escort carrier | ex-Rio Hudson |
| March 2 | Royal Navy | Biter (D97) | Avenger-class escort carrier | ex-Rio Parana |
| March 3 | United States Navy | Charger (AVG-30) | Charger-class escort carrier | ex-Rio de la Plata |
| March 4 | United States Navy | Aaron Ward (DD-483) | Gleaves-class destroyer | under command of Commander Orville F. Gregor [1] |
| March 20 | United States Navy | South Dakota (BB-57) | South Dakota-class battleship | |
| March | Royal Navy | Maria | Wreck dispersal vessel | ex-German weather ship WBS 8 August Wriedt |
| April 30 | United States Navy | Indiana (BB-58) | South Dakota-class battleship | |
| May 1 | Luftwaffe | Bussard | Bussard-class seaplane tender | Completion date |
| May 12 | United States Navy | Marcasite (PY-28) | Patrol yacht | ex-Ramfis [2] |
| May 12 | United States Navy | Massachusetts (BB-59) | South Dakota-class battleship | |
| June 3 | Royal Navy | Invicta | Landing Ship, Infantry | ex-SS Invicta for Southern Railway, requisitioned on completion |
| June 15 | United States Navy | Copahee (CVE-12) | Bogue-class escort carrier | ex-Steel Architect |
| June 22 | Royal Navy | Anson (79) | King George V-class battleship | |
| July 1 | Royal Navy | Dasher (D37) | Avenger-class escort carrier | ex-Rio de Janeiro |
| August 9 | Kriegsmarine | Schnelles Geleitboot 1 | Sans Souci-class sloop | SG 1 |
| August 16 | United States Navy | Alabama (BB-60) | South Dakota-class battleship | |
| August 20 | United States Navy | Nassau (CVE-16) | Bogue-class escort carrier | |
| August 21 | United States Navy | Chenango (ACV-28) | Sangamon-class escort carrier | recommissioned after conversion |
| August 25 | United States Navy | Sangamon (ACV-26) | Sangamon-class escort carrier | recommissioned after conversion |
| August 29 | Royal Navy | Howe (32) | King George V-class battleship | |
| August 31 | United States Navy | Direct (AM-90) | Adroit-class minesweeper | |
| September 7 | Kriegsmarine | Schnelles Geleitboot 2 | Sans Souci-class sloop | SG 2 |
| September 15 | United States Navy | Altamaha (CVE-18) | Bogue-class escort carrier | |
| September 19 | United States Navy | Chenango (ACV-28) | Sangamon-class escort carrier | recommissioned after conversion |
| September 24 | United States Navy | Suwannee (ACV-27) | Sangamon-class escort carrier | recommissioned after conversion |
| September 26 | United States Navy | Bogue (CVE-9) | Bogue-class escort carrier | ex-Steel Advocate |
| September 30 | Royal Navy | Attacker (D02) | Attacker-class escort carrier | ex-USS Barnes, acquired through Lend-Lease |
| November 2 | Kriegsmarine | Schnelles Geleitboot 3 | Sans Souci-class sloop | SG 3 |
| November 8 | United States Navy | Card (CVE-11) | Bogue-class escort carrier | |
| November 15 | Royal Navy | Battler (D18) | Attacker-class escort carrier | ex-USS Altamaha, acquired through Lend-Lease |
| November 22 | Luftwaffe | Falke | Bussard-class seaplane tender | completion date |
| 12 December | United States Navy | Apache (ATF-67) | Cherokee-class tugboat | |
| December 21 | Royal Navy | Stalker (D91) | Attacker-class escort carrier | ex-USS Hamlin, acquired through Lend-Lease |
| December 10 | United States Navy | Core (CVE-13) | Bogue-class escort carrier | |
| December 31 | United States Navy | Essex (CV-9) | Essex-class aircraft carrier | |
| December | Luftwaffe | Boelcke | Karl Meyer-class seaplane tender | completion date |
| unknown date | Kriegsmarine | Kehdingen | Weather ship | WBS 6 |