| Locality | Post Code |
|---|---|
| Bosanska Gradiška, Gradiška | 78400 |
| Cerovljani, Gradiška | 78403 |
| Dubrave, Gradiška | 78411 |
| Gornji Podgradci, Gradiška | 78405 |
| Kočićevo, Gradiška | 78409 |
| Kukulje, Gradiška | 78424 |
| Laminci-Sređani, Gradiška | 78407 |
| Mašići, Gradiška | 78410 |
| Nova Topola, Gradiška | 78418 |
| Orahova, Gradiška | 78406 |
| Turjak, Gradiška | 78404 |
| Vrbaška, Gradiška | 78408 |