| Place | Postal Code |
|---|---|
| 粟又 (Awamata, Chiba) | 298-0277 |
| 馬場内 (Babauchi, Chiba) | 298-0231 |
| 笛倉 (Fuegura, Chiba) | 298-0233 |
| 船子 (Funako, Chiba) | 298-0204 |
| 原内 (Harauchi, Chiba) | 298-0237 |
| 部田 (Heta, Chiba) | 298-0226 |
| 平沢 (Hirasawa, Chiba) | 298-0254 |
| 堀切 (Horikiri, Chiba) | 298-0262 |
| 堀之内 (Horinochi, Chiba) | 298-0224 |
| 市川 (Ichikawa, Chiba) | 298-0272 |
| 伊保田 (Ihota, Chiba) | 298-0263 |
| 石神 (Ishigami, Chiba) | 298-0256 |
| 板谷 (Itaya, Chiba) | 298-0261 |
| 会所 (Kaisho, Chiba) | 298-0276 |
| 紙敷 (Kamishiki, Chiba) | 298-0241 |
| 川畑 (Kawahata, Chiba) | 298-0253 |
| 小内 (Kochi, Chiba) | 298-0232 |
| 小内笛倉入会 (Kochifuegurairiai, Chiba) | 298-0238 |
| 小苗 (Komyo, Chiba) | 298-0242 |
| 小田代 (Kotadai, Chiba) | 298-0265 |
| 紺屋 (Koya, Chiba) | 298-0211 |
| 小谷松 (Koyamatsu, Chiba) | 298-0228 |
| 小沢又 (Kozawamata, Chiba) | 298-0278 |
| 久保 (Kubo, Chiba) | 298-0215 |
| 久我原 (Kugahara, Chiba) | 298-0251 |
| 黒原 (Kurohara, Chiba) | 298-0255 |
| 葛藤 (Kuzufuji, Chiba) | 298-0267 |
| 松尾 (Matsuo, Chiba) | 298-0244 |
| 三又 (Mimata, Chiba) | 298-0252 |
| 百鉾 (Mofuku, Chiba) | 298-0236 |
| Postal Codes in Isumi | |
|---|---|
| Onjuku (御宿町) | |
| Otaki (大多喜町) | |