557 Coast Regiment RA was formed as 19 Coast Artillery Group RA at St Austell with five batteries, in October 1940. It was re-designated 557 Coast Regiment RA in June 1941. RHQ was disbanded in April 1944 and the batteries dispersed.
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.
| Oct 40 | Formed as 19 Coast Artillery Group | St Austell, Cornwall, UK | |
| Oct 40 |  |
Southern Command | St Austell, Cornwall, UK |
| Jun 41 | Became 557 Coast Regiment | St Austell, Cornwall, UK | |
| Nov 42 | Home Forces | Lostwithiel, Cornwall, UK | |
| Apr 44 | Disbanded |
Batteries
| Oct 40 | 364, 392, 393, 396, 397 |
| Mar 41 | 212, 214, 364, 392, 393, 396, 397 |
| Aug 42 | 212, 214, 379 (Appledore), 393, 394 |
| Oct 42 | 212, 214, 364 (Appledore), 379, 393, 394, 398 (Instow) |
| Mar 43 | 212, 364, 379, 393, 394 |