Gampaha's 2026 population is now estimated at 69,141. In 2025, the population of Gampaha was 68,631. Gampaha has grown by 510 in the last year, which represents a 0.74% annual change. These population values and projections come from World Population Review Internal Projections .
| City | 2026 Pop. ↓ | Growth |
|---|---|---|
| Colombo | 468,377 | -1.28% |
| Kaduwela (Battaramulla) | 319,383 | 1.71% |
| Maharagama | 211,706 | 0.54% |
| Negombo | 174,048 | 1.44% |
| Moratuwa | 157,164 | -0.49% |
| Dehiwala-Mount Lavinia | 155,896 | -1.19% |
| Kalmunai (incl. Sainthamarathu) | 107,090 | 0.5% |
| Sri Jayawardenepura | 98,062 | -0.68% |
| Batticaloa | 94,388 | 0.65% |
| Kandy | 86,895 | -0.91% |
| Galle | 81,570 | -0.4% |
| Matara | 71,650 | -0.25% |
| Gampaha | 69,141 | 0.74% |
| Jaffna | 68,075 | -1.22% |
| Gampola | 66,672 | 4.12% |
| Kolonnawa | 66,612 | 0.74% |
| Puttalam | 50,775 | 0.79% |
| Trincomalee | 50,293 | 0.28% |
| Kattankudy (Kathankudi) | 48,819 | 1.37% |
| Ratnapura | 48,305 | 0.18% |
| Katunayake (-Seeduwa) | 48,118 | -1.67% |
| Anuradhapura | 47,519 | -0.45% |
| Hambantota | 46,792 | 5.13% |
| Seethawakapura (Avissawella) | 46,650 | 3.13% |
| Beruwala | 44,821 | 1.23% |
| Badulla | 43,859 | 0.27% |
| Matale | 36,476 | 0% |
| Ja-Ela | 31,647 | 0.09% |
| Ampara | 30,014 | 2.08% |
| Wattala-Mabole | 27,020 | -0.26% |
| Kalutara | 26,977 | -1.3% |
| Panadura | 26,274 | -0.96% |
| Kadugannawa | 25,482 | 5.13% |
| Peliyagoda | 25,228 | -0.68% |
| Balangoda | 24,617 | 2.89% |
| Weligama | 23,156 | 0.24% |
| Nuwara Eliya | 21,930 | -0.58% |
| Kurunegala | 20,933 | -1.21% |
| Ambalangoda | 20,339 | 0.12% |
| Vavuniya | 20,325 | -3.77% |
| Chilaw | 18,472 | -1.06% |
| Hatton-Dickoya | 15,016 | 0.21% |
| Kegalle | 14,645 | -0.62% |
| Nawalapitiya | 13,094 | -0.13% |
| Horana | 10,086 | 0.39% |
| Wattegama | 8,575 | 0.36% |
| Minuwangoda | 7,363 | -0.16% |
| Tangalle | 6,482 | -1.89% |
| Thalawakele-Lindula | 6,246 | 2.08% |
| Haputale | 6,013 | 0.92% |
| Kuliyapitiya | 4,569 | -1.32% |
