| Place | Post Code |
|---|---|
| Maporong, Oas | 4505 |
| Maramba, Oas | 4505 |
| Matambo, Oas | 4505 |
| Mayag, Oas | 4505 |
| Mayao, Oas | 4505 |
| Moroponros, Oas | 4505 |
| Nagas, Oas | 4505 |
| Obaliw-Rinas, Oas | 4505 |
| Pistola, Oas | 4505 |
| Ramay, Oas | 4505 |
| Rizal, Oas | 4505 |
| Saban, Oas | 4505 |
| San Agustin, Oas | 4505 |
| San Antonio, Oas | 4505 |
| San Isidro, Oas | 4505 |
| San Jose, Oas | 4505 |
| San Juan, Oas | 4505 |
| San Miguel, Oas | 4505 |
| San Pascual, Oas | 4505 |
| San Ramon, Oas | 4505 |
| San Vicente, Oas | 4505 |
| Tablon, Oas | 4505 |
| Talisay, Oas | 4505 |
| Talongog, Oas | 4505 |
| Tapel, Oas | 4505 |
| Tobgon, Oas | 4505 |