3 Medium Brigade was re-designated 3 Medium Regiment RA in May 1938. It was re-organised with two batteries in February 1939. In April 1947 the Regiment was re-designated 15 Medium Regiment RA.
| 3 Sep 39 | Southern Command | Larkhill, Wiltshire, UK |
| Oct 39 | 1 Corps | France |
| Jun 40 | Home Forces | UK |
| May 43 | Middle East Forces | N Africa |
| Jul 44 | 8 Army | Italy |
| May 45 | 2 Army | NW Europe |
Batteries
| Sep 39 | 2/11, 6/10 |
Equipment
| Sep 39 | 6 inch Howitzer |
