Negros Occidental is composed of a total 33 municipalities and cities combined including the very famous Bacolod City. Below is a list of the zip or postal codes:
| Location | Zip Code |
| Bacolod City | 6100 |
| Bago City | 6101 |
| Binalbagan City | 6107 |
| Cadiz City | 6121 |
| Calatrava | 6126 |
| Candoni | 6110 |
| Enrique Magalona | 6118 |
| Escalante City | 6124 |
| Himamaylan City | 6108 |
| Hinigaran City | 6106 |
| Hinoba-an | 6114 |
| Ilog | 6109 |
| Isabela | 6128 |
| Kabankalan City | 6111 |
| Kauayan | 6112 |
| La Carlota City | 6130 |
| La Castillana | 6131 |
| Manapla | 6120 |
| Moises Padilla | 6132 |
| Murcia | 6129 |
| Paraiso (Fabrica) | 6123 |
| Pontevedra | 6105 |
| Pulupandan | 6102 |
| Sagay City | 6122 |
| San Carlos City | 6127 |
| San Enrique | 6104 |
| Silay City | 6116 |
| Silay Hawaiian Central | 6117 |
| Sipalay City | 6113 |
| Talisay City | 6115 |
| Toboso | 6125 |
| Valladolid | 6103 |
| Victorias City | 6119 |