40 Light Anti-Aircraft Regiment RA(TA) was formed at Inverness in September 1939. It was placed in suspended animation in March 1946 and re-constituted as 540 Light Anti-Aircraft Regiment RA(TA) in January 1947.
| Sep 39 | Formed | Inverness, Inverness-shire, UK |
| Feb 41 | 51 Anti-Aircraft Brigade | North East Scotland |
| May 42 | 51 Infantry Division | UK |
| Aug 42 | 51 Infantry Division | N Africa |
| Jul 43 | 51 Infantry Division | Sicily |
| Nov 43 | 51 Infantry Division | UK |
| Jun 44 | 51 Infantry Division | NW Europe |
Batteries
| Sep 39 | 105, 140 |
| Nov 39 | 105, 140, 177 |
| Sep 41 | 105, 140, 268 |
