| Locality | Post Code |
|---|---|
| Kisagami (大分市) | 879-2113 |
| Kitashimogori (大分市) | 870-0927 |
| Kitatsurusaki (大分市) | 870-0102 |
| Kobarudanchi (大分市) | 870-1134 |
| Koendori (大分市) | 870-0173 |
| Koendorinishi (大分市) | 870-0174 |
| Kogazuru (大分市) | 870-0935 |
| Koikebaru (大分市) | 870-0147 |
| Kokubu (大分市) | 870-0864 |
| Kokubudai (大分市) | 870-0863 |
| Kokubudanchi (大分市) | 870-0865 |
| Kokubushimmachi (大分市) | 870-0869 |
| Kotobukimachi (大分市) | 870-0036 |
| Kozai (大分市) | 870-0327 |
| Kubaru (大分市) | 870-0304 |
| Kubaruchuo (大分市) | 870-0325 |
| Kubarukita (大分市) | 870-0324 |
| Kubaruminami (大分市) | 870-0326 |
| Kuchido (大分市) | 870-1162 |
| Kudo (大分市) | 870-0314 |
| Kyogaokaminami (大分市) | 870-0129 |
| Madokoro (大分市) | 870-0268 |
| Magari (大分市) | 870-0946 |
| Maizurumachi (大分市) | 870-0044 |
| Maki (大分市) | 870-0924, 870-0152 |
| Makikamimachi (大分市) | 870-0925 |