The canton Cherbourg-en-Cotentin-3 has 10 communes.
| Code | Name | Population ▼ |
|---|---|---|
| 50129 | Cherbourg-en-Cotentin | 78 258 |
| 50599 | Tollevast | 1 654 |
| 50294 | Martinvast | 1 348 |
| 50149 | Couville | 1 249 |
| 50594 | Teurthéville-Hague | 1 037 |
| 50230 | Hardinvast | 928 |
| 50575 | Sideville | 856 |
| 50643 | Virandeville | 816 |
| 50382 | Nouainville | 607 |
| 50519 | Saint-Martin-le-Gréard | 606 |