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 was considered a War Formed Regiment in January 1947 and re-designated as 105 Heavy Anti-Aircraft Regiment RA in April that year.
| Feb 42 | Formed | Wirral, UK |
| Apr 42 | 33 Anti-Aircraft Brigade, 4 Anti-Aircraft Division | North West England |
| Sep 42 | 44 Anti-Aircraft Brigade, 4 Anti-Aircraft Group | North West England |
| Jun 43 | 30 Anti-Aircraft Brigade, 6 Anti-Aircraft Group | North East & Scotland |
| Apr 44 | 30 Anti-Aircraft Brigade, 5 Anti-Aircraft Group | 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) |
