The canton Portet-sur-Garonne has 12 communes.
| Code | Name | Population ▼ |
|---|---|---|
| 31433 | Portet-sur-Garonne | 9 782 |
| 31248 | Labarthe-sur-Lèze | 6 585 |
| 31165 | Eaunes | 6 539 |
| 31458 | Roques | 5 436 |
| 31421 | Pins-Justaret | 4 378 |
| 31460 | Roquettes | 4 280 |
| 31574 | Vernet | 3 381 |
| 31263 | Lagardelle-sur-Lèze | 3 303 |
| 31572 | Venerque | 2 974 |
| 31420 | Pinsaguel | 2 786 |
| 31533 | Saubens | 2 364 |
| 31580 | Villate | 1 233 |