| Place | Post Code |
|---|---|
| Apuao, Mercedes | 4601 |
| Barangay I, Mercedes | 4601 |
| Barangay II, Mercedes | 4601 |
| Barangay III, Mercedes | 4601 |
| Barangay IV, Mercedes | 4601 |
| Barangay V, Mercedes | 4601 |
| Barangay VI, Mercedes | 4601 |
| Barangay VII, Mercedes | 4601 |
| Caringo, Mercedes | 4601 |
| Catandunganon, Mercedes | 4601 |
| Cayucyucan, Mercedes | 4601 |
| Colasi, Mercedes | 4601 |
| Del Rosario, Mercedes | 4601 |
| Gaboc, Mercedes | 4601 |
| Hamoraon, Mercedes | 4601 |
| Hinipaan, Mercedes | 4601 |
| Lalawigan, Mercedes | 4601 |
| Lanot, Mercedes | 4601 |
| Mambungalon, Mercedes | 4601 |
| Manguisoc, Mercedes | 4601 |
| Masalongsalong, Mercedes | 4601 |
| Matoogtoog, Mercedes | 4601 |
| Pambuhan, Mercedes | 4601 |
| Quinapaguian, Mercedes | 4601 |
| San Roque, Mercedes | 4601 |
| Tarum, Mercedes | 4601 |