| Place | Post Code |
|---|---|
| Ricarte Norte, Diffun | 3401 |
| Ricarte Sur, Diffun | 3401 |
| Rizal, Diffun | 3401 |
| San Antonio, Diffun | 3401 |
| San Isidro, Diffun | 3401 |
| San Pascual, Diffun | 3401 |
| Villa Pascua, Diffun | 3401 |
| All postal codes in Quirino | |
|---|---|
| Aglipay, Quirino | |
| Cabarroguis, Quirino | |
| Diffun, Quirino | |
| Maddela, Quirino | |
| Nagtipunan, Quirino | |
| Saguday, Quirino | |