| Gampaha District | area km2 | population (2001) |
| Negombo | 50 | 144,274 |
| Katana | 116 | 122,683 |
| Divulapitiya | 202 | 128,048 |
| Mirigama | 183 | 143,663 |
| Attanagalla | 149 | 154,967 |
| Minuwangoda | 128 | 151,661 |
| Wattala | 54 | 160,127 |
| Ja-Ela | 60 | 184,665 |
| Gampaha | 96 | 171,040 |
| Mahara/Kadawatha | 94 | 176,670 |
| Dompe | 176 | 130,021 |
| Biyagama | 59 | 161,300 |
| Kelaniya | 20 | 134,364 |