| Locality | Post Code |
|---|---|
| Dale, Caldwell | 78616 |
| Fentress, Caldwell | 78622 |
| Joliet, Caldwell | 78648 |
| Lockhart, Caldwell | 78644 |
| Luling, Caldwell | 78648 |
| Lytton Springs, Caldwell | 78616 |
| Martindale, Caldwell | 78655 |
| Maxwell, Caldwell | 78656 |
| McMahan, Caldwell | 78616 |
| Mendoza, Caldwell | 78644 |
| Prairie Lea, Caldwell | 78661 |
| Reedville, Caldwell | 78656 |
| Seawillow, Caldwell | 78644 |
| Stairtown, Caldwell | 78648 |
| Tilmon, Caldwell | 78616 |