120 Heavy Anti-Aircraft Regiment RA (TA) was formed at Lawrenny Castle in January 1941. The Regiment served in Anti-Aircraft Command until January 1943. It moved to Egypt in May 1943 and later to Cyprus. 120 Heavy Anti-Aircraft Regiment RA (TA)was disbanded in June 1944.
Illustrations of the formation badges under which a unit served or supported are given. This is no guarantee that the unit used this formations badge.
| Jan 41 | Formed | Lawrenny Castle, Pembrokeshire, UK |
|
| Jan 41 |  |
9 Anti-Aircraft Division, 61 Anti-Aircraft Brigade | Pembroke, Pembrokeshire, UK |
| Aug 41 |  |
1 Anti-Aircraft Division, 26 Anti-Aircraft Brigade | London, UK |
| Jan 43 |  |
War Office Reserve | UK |
| May 43 |  |
Middle East Forces | Port Tewfik, Egypt |
| Jun 43 |  |
9 Army, 20 Anti-Aircraft Brigade, | Cyprus |
| Oct 43 | Regiment “Diluted” by Basuto troops of the African Pioneer Corps | Cyprus | |
| Jun 44 | Disbanded |
Batteries
| Jan 41 | 381, 384, 386 |
| Aug 41 | 248, 381, 384, 386 |
| Oct 42 | 248, 381, 384 |
Gun Sites Occupied
384 Battery
| Dates | Gun Site | Under Command | Gun Defended Area |
| Mar 41 | O1 Royal Ordnance Factory Pembrey P9 West Pennar |
79 HAA Rgt | Milford Haven |
| Mar 41 | O2 Llanelli N12 Temporary site |
79 HAA Rgt | Swansea |
| 5 Apr 41 | N12 Temporary site N9 Bryn |
79 HAA Rgt | Swansea |
| May-Aug 41 | N7 Briton Ferry N9 Bryn |
79 HAA Rgt | Swansea |
386 Battery
| Dates | Gun Site | Gun Defended Area |
| May-Aug 41 | N3A Jersey Marine (2 sections) | Swansea |