| Locality | Post Code |
|---|---|
| Alamo, Contra Costa | 94507 |
| Antioch, Contra Costa | 94509, 94531 |
| Bay Point, Contra Costa | 94565 |
| Bethel Island, Contra Costa | 94511 |
| Blackhawk, Contra Costa | 94506 |
| Brentwood, Contra Costa | 94513 |
| Briones, Contra Costa | 94553 |
| Byron, Contra Costa | 94514 |
| Canyon, Contra Costa | 94516 |
| Clayton, Contra Costa | 94517 |
| Clyde, Contra Costa | 94520 |
| Concord, Contra Costa | 94518, 94519, 94520, 94521 |
| Crockett, Contra Costa | 94525 |
| Danville, Contra Costa | 94506, 94526 |
| Diablo, Contra Costa | 94528 |
| Discovery Bay, Contra Costa | 94505 |
| El Cerrito, Contra Costa | 94530 |
| El Sobrante, Contra Costa | 94803 |
| Hercules, Contra Costa | 94547 |
| Hilltop Mall, Contra Costa | 94806 |
| Kensington, Contra Costa | 94706, 94707, 94708 |
| Knightsen, Contra Costa | 94548 |
| Lafayette, Contra Costa | 94549, 94595, 94597 |
| Martinez, Contra Costa | 94553 |
| Moraga, Contra Costa | 94556 |
| North Richmond, Contra Costa | 94801 |