| Locality | Postal Code |
|---|---|
| Hachimammachi (天草市) | 863-0047 |
| Hajiutomachi (天草市) | 863-0045 |
| Hamasakimachi (天草市) | 863-0018 |
| Higashihamamachi (天草市) | 863-0014 |
| Higashimachi (天草市) | 863-0033 |
| Hommachi Hon (天草市) | 863-0007 |
| Hommachi Shimogawachi (天草市) | 863-0006 |
| Hommachi Shinkyu (天草市) | 863-0005 |
| Hondomachi Hirose (天草市) | 863-0001 |
| Hondomachi Hondo (天草市) | 863-0003 |
| Hondomachi Hontobaba (天草市) | 863-0002 |
| Hondomachi Motoizumi (天草市) | 863-0004 |
| Imagamamachi (天草市) | 863-0012 |
| Imagamashimmachi (天草市) | 863-0013 |
| Itsuwamachi Futae (天草市) | 863-2421 |
| Itsuwamachi Goryo (天草市) | 863-2201 |
| Itsuwamachi Jogawara (天草市) | 863-2114 |
| Itsuwamachi Oniike (天草市) | 863-2331 |
| Itsuwamachi Teno (天草市) | 863-2424 |
| Jokamachi (天草市) | 863-0016 |
| Jonammachi (天草市) | 863-0034 |
| Kamebamachi Jikiba (天草市) | 863-0046 |
| Kamebamachi Kamegawa (天草市) | 863-0043 |
| Kawaramachi (天草市) | 863-0024 |
| Kawarashimmachi (天草市) | 863-0036 |
| Kawauramachi Hisadome (天草市) | 863-1214 |