The canton L'Isle-Adam has 15 communes.
| Code | Name | Population ▼ |
|---|---|---|
| 95487 | Persan | 14 359 |
| 95313 | L'Isle-Adam | 12 493 |
| 95052 | Beaumont-sur-Oise | 10 232 |
| 95480 | Parmain | 5 655 |
| 95134 | Champagne-sur-Oise | 5 036 |
| 95116 | Bruyères-sur-Oise | 4 921 |
| 95504 | Presles | 4 017 |
| 95026 | Asnières-sur-Oise | 3 127 |
| 95058 | Bernes-sur-Oise | 2 684 |
| 95436 | Mours | 1 693 |
| 95529 | Ronquerolles | 907 |
| 95452 | Nointel | 903 |
| 95678 | Villiers-Adam | 858 |
| 95445 | Nerville-la-Forêt | 756 |
| 95456 | Noisy-sur-Oise | 549 |