141 (Mixed) Heavy Anti-Aircraft Regiment RA (TA) was formed at Croydon in December 1941. It became a non-mixed Regiment in February 1946. The Regiment served in Anti-Aircraft Command for its entire war. 141 (Mixed) Heavy Anti-Aircraft Regiment RA (TA) was considered a War Formed Regiment in January 1947 at White Abbey, Belfast and re-designated as 99 Heavy Anti-Aircraft Regiment RA in April that year.
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.
| Dec 41 | Formed | Croydon, London | |
| Dec 41 |  |
1 Anti-Aircraft Division, 48 Anti-Aircraft Brigade | London, UK |
| Jan 42 | |
1 Anti-Aircraft Division, 49 Anti-Aircraft Brigade | London, UK |
| Dec 43 |  |
7 Anti-Aircraft Group | Belfast |
Batteries
| Jan 42 | 486, 489, 490 |
| Mar 42 | 486, 490, 493, 499 |
| Feb 44 | 486, 490, 493 |