| Locality | Post Code |
|---|---|
| Banks Springs, Caldwell | 71418 |
| Bellview, Caldwell | 71418 |
| Big Ridge, Caldwell | 71418 |
| Brownville, Caldwell | 71418 |
| Burroughs, Caldwell | 71418 |
| Clarks, Caldwell | 71415 |
| Columbia, Caldwell | 71418 |
| Columbia Heights, Caldwell | 71418 |
| Copenhagen, Caldwell | 71418 |
| Duty Ferry, Caldwell | 71418 |
| Eastside, Caldwell | 71418 |
| Grayson, Caldwell | 71435 |
| Hearn Island, Caldwell | 71418 |
| Hebert, Caldwell | 71418 |
| Kelly, Caldwell | 71441 |
| Longlake, Caldwell | 71418 |
| Riverton, Caldwell | 71418 |
| Vixen, Caldwell | 71418 |