| Source | UN (World Urbanization Prospects 2018) |
| Date | 08 Mar 2025 |
| Code | City | Population | Share (%) | Rank | Change | |||
|---|---|---|---|---|---|---|---|---|
| 2024 | 2025 | Thailand | World | Population | (%) | |||
| Krun | Krung Thep (Bangkok) | 11,233,869 | 11,391,704 | 15.9 | 1 | 32 | 157,835 | 1.40 |
| Chon | Chon Buri | 1,472,709 | 1,491,184 | 2.08 | 2 | 406 | 18,475 | 1.25 |
| Samu | Samut Prakan | 1,376,146 | 1,393,409 | 1.95 | 3 | 436 | 17,263 | 1.25 |
| Chia | Chiang Mai | 1,228,773 | 1,244,187 | 1.74 | 4 | 511 | 15,414 | 1.25 |
| Song | Songkhla | 1,017,784 | 1,030,552 | 1.44 | 5 | 628 | 12,768 | 1.25 |
| Nont | Nonthaburi | 1,013,672 | 1,026,388 | 1.43 | 6 | 630 | 12,716 | 1.25 |
| Path | Pathum Thani | 962,126 | 974,195 | 1.36 | 7 | 674 | 12,069 | 1.25 |
| Nakh | Nakhon Ratchasima | 811,446 | 821,187 | 1.15 | 8 | 786 | 9,741 | 1.20 |
| Samu | Samut Sakhon | 608,895 | 616,533 | 0.861 | 9 | 1055 | 7,638 | 1.25 |
| Udon | Udon Thani | 597,070 | 604,163 | 0.844 | 10 | 1085 | 7,093 | 1.19 |
| Chia | Chiang Rai | 579,088 | 586,352 | 0.819 | 11 | 1130 | 7,264 | 1.25 |
| Rayo | Rayong | 566,647 | 573,756 | 0.801 | 12 | 1156 | 7,109 | 1.25 |
| Nakh | Nakhon Pathom | 556,973 | 567,386 | 0.792 | 13 | 1166 | 10,413 | 1.87 |
| Kala | Kalasin | 545,045 | 551,882 | 0.771 | 14 | 1197 | 6,837 | 1.25 |
| Khon | Khon-Kaen | 529,208 | 535,847 | 0.748 | 15 | 1230 | 6,639 | 1.25 |
| Sura | Surat Thani | 522,231 | 528,783 | 0.738 | 16 | 1246 | 6,552 | 1.25 |
| Ubon | Ubon Ratchathani | 521,070 | 527,549 | 0.737 | 17 | 1248 | 6,479 | 1.24 |
| Lop | Lop Buri | 511,097 | 524,118 | 0.732 | 18 | 1259 | 13,021 | 2.55 |
| Buri | Buri Ram | 477,774 | 483,767 | 0.675 | 19 | 1348 | 5,993 | 1.25 |
| Lamp | Lampang | 473,282 | 479,219 | 0.669 | 20 | 1363 | 5,937 | 1.25 |
| Phra | Phra Nakhon Si Ayutthaya | 464,617 | 470,442 | 0.657 | 21 | 1386 | 5,825 | 1.25 |
| Roi | Roi Et | 463,940 | 469,760 | 0.656 | 22 | 1392 | 5,820 | 1.25 |
| Phuk | Phuket | 455,102 | 460,810 | 0.643 | 23 | 1422 | 5,708 | 1.25 |
| Ratc | Ratchaburi | 432,804 | 438,953 | 0.613 | 24 | 1487 | 6,149 | 1.42 |
| Sako | Sakon Nakhon | 401,263 | 406,297 | 0.567 | 25 | 1577 | 5,034 | 1.25 |
| Chan | Chanthaburi | 398,730 | 406,188 | 0.567 | 26 | 1578 | 7,458 | 1.87 |
| Suph | Suphan Buri | 373,430 | 380,383 | 0.531 | 27 | 1671 | 6,953 | 1.86 |
| Lamp | Lamphun | 333,976 | 338,166 | 0.472 | 28 | 1807 | 4,190 | 1.25 |