The region Brittany has 15 arrondissements.
| Code ▲ | Name | Administrative seat | Department | Com. |
|---|---|---|---|---|
| 221 | Dinan | Dinan | 22 | 66 |
| 222 | Guingamp | Guingamp | 22 | 111 |
| 223 | Lannion | Lannion | 22 | 57 |
| 224 | Saint-Brieuc | Saint-Brieuc | 22 | 110 |
| 291 | Brest | Brest | 29 | 77 |
| 292 | Châteaulin | Châteaulin | 29 | 57 |
| 293 | Morlaix | Morlaix | 29 | 59 |
| 294 | Quimper | Quimper | 29 | 84 |
| 351 | Fougères-Vitré | Fougères | 35 | 105 |
| 352 | Redon | Redon | 35 | 50 |
| 353 | Rennes | Rennes | 35 | 109 |
| 354 | Saint-Malo | Saint-Malo | 35 | 68 |
| 561 | Lorient | Lorient | 56 | 58 |
| 562 | Pontivy | Pontivy | 56 | 92 |
| 563 | Vannes | Vannes | 56 | 99 |