Udon Thani's 2026 population is now estimated at 611,342. In 1950, the population of Udon Thani was 16,129. Udon Thani has grown by 7,179 in the last year, which represents a 1.19% annual change. These population estimates and projections come from the latest revision of the UN World Urbanization Prospects . These estimates represent the Urban agglomeration of Udon Thani, which typically includes Udon Thani's population in addition to adjacent suburban areas.
| City | 2026 Pop. ↓ | Growth |
|---|---|---|
| Bangkok | 11,543,900 | 1.34% |
| Chon Buri | 1,509,580 | 1.23% |
| Samut Prakan | 1,410,600 | 1.23% |
| Chiang Mai | 1,259,540 | 1.23% |
| Songkhla | 1,043,260 | 1.23% |
| Pathum Thani | 986,213 | 1.23% |
| Nakhon Ratchasima | 831,016 | 1.2% |
| Samut Sakhon | 624,139 | 1.23% |
| Chiang Rai | 593,585 | 1.23% |
| Rayong | 580,833 | 1.23% |
| Nakhon Pathom | 576,756 | 1.65% |
| Kalasin | 558,690 | 1.23% |
| Surat Thani | 535,306 | 1.23% |
| Lop Buri | 535,183 | 2.11% |
| Ubon Ratchathani | 534,017 | 1.23% |
| Buri Ram | 489,735 | 1.23% |
| Lampang | 485,131 | 1.23% |
| Phra Nakhon Si Ayutthaya | 476,244 | 1.23% |
| Roi Et | 475,554 | 1.23% |
| Phuket | 466,495 | 1.23% |
| Ratchaburi | 444,864 | 1.35% |
| Chanthaburi | 412,898 | 1.65% |
| Sakon Nakhon | 411,309 | 1.23% |
| Suphan Buri | 386,646 | 1.65% |
| Lamphun | 342,337 | 1.23% |
