156 (Mixed) Heavy Anti-Aircraft Regiment RA (TA) was formed in London in April 1942. It became a non-mixed Regiment in April 1946. The Regiment served with Anti-Aircraft Command in the London IAZ for its entire war. 156 (Mixed) Heavy Anti-Aircraft Regiment RA (TA) was considered a War Formed Regiment in January 1947 and re-designated as 112 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.
| Apr 42 | Formed | London, UK | |
| Apr 42 |  |
1 Anti-Aircraft Division, 26 Anti-Aircraft Brigade | London, UK |
| Oct 42 |  |
1 Anti-Aircraft Group, 26 Anti-Aircraft Brigade | London, UK |
| Re-organised 1946 |
Batteries
| Apr 42 | 530 (Mixed), 532 (Mixed), 533 (Mixed), 535 (Mixed) |