149 (Mixed) Heavy Anti-Aircraft Regiment RA (TA) was formed on the Wirral in February 1942. It became a non-mixed Regiment in August 1945. The Regiment served its entire time in Anti-Aircraft Command. 149 (Mixed) Heavy Anti-Aircraft Regiment RA (TA) was considered a War Formed Regiment in January 1947 and re-designated as 105 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.
| Feb 42 | Formed | Wirral, UK | |
| Apr 42 |  |
4 Anti-Aircraft Division, 33 Anti-Aircraft Brigade | North West England |
| Sep 42 |  |
4 Anti-Aircraft Group, 44 Anti-Aircraft Brigade | North West England |
| Jun 43 | |
6 Anti-Aircraft Group, 30 Anti-Aircraft Brigade | North East & Scotland |
| Apr 44 | |
5 Anti-Aircraft Group, 30 Anti-Aircraft Brigade | Eastern England |
Batteries
| Feb 42 | 506 (Mixed), 507 (Mixed), 512 (Mixed) |
| Sep 42 | 506 (Mixed), 507 (Mixed), 512 (Mixed), 581 (Mixed) |
| Apr 44 | 506 (M), 507 (M), 512 (M) |