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 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.
| Dec 41 | Formed | Croydon, London |
| Dec 41 | 48 Anti-Aircraft Brigade, 1 Anti-Aircraft Division | London, UK |
| Jan 42 | 49 Anti-Aircraft Brigade, 1 Anti-Aircraft Division | London, UK |
Batteries
| Jan 42 | 486, 489, 490 |
| Mar 42 | 486, 490, 493, 499 |
| Feb 44 | 486, 490, 493 |
