81 Anti-Tank Regiment RA was formed in September 1941 at Woodhall Spa with four batteries from different regiments. The Regiment was disbanded in April 1945.
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.
| Sep 41 | Formed from 21, 59, 62 & 66 Anti-Tank Regiments | Woodhall Spa, Lincolnshire, UK | |
| Sep 41 | Home Forces | UK | |
| Nov 41 |  |
1 Infantry Division | UK |
| Mar 43 | |
1 Infantry Division | N Africa |
| Jun 43 | |
1 Infantry Division | Pantelleria |
| Jun 43 | |
1 Infantry Division | N Africa |
| Dec 43 | |
1 Infantry Division | Italy |
| Jan 44 | |
1 Infantry Division | Anzio, Italy |
| Feb 45 | |
1 Infantry Division | Palestine |
| Apr 45 | Disbanded |
Batteries
| Sep 41 | BB, 291, 294, 297 |
| Jun 42 | BB, 294, 297 |
| Jul 43 | BB, 294, 297, 328 |