26 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Plano | 1 | 296,718 | 286,422 | 0.58% | 4,138 | 72 | City |
| Frisco | 2 | 251,430 | 202,764 | 3.33% | 3,666 | 69 | City |
| McKinney | 3 | 242,534 | 197,510 | 3.19% | 3,531 | 69 | City |
| Allen | 4 | 117,841 | 105,556 | 1.77% | 4,466 | 26 | City |
| Celina | 5 | 68,583 | 17,816 | 14.07% | 1,398 | 49 | City |
| Wylie | 6 | 65,489 | 57,883 | 1.97% | 3,095 | 21 | City |
| Prosper | 7 | 51,345 | 30,818 | 7.14% | 2,035 | 25 | Town |
| Princeton | 8 | 46,744 | 17,569 | 11.61% | 3,241 | 14 | City |
| Anna | 9 | 39,203 | 17,552 | 10.14% | 2,199 | 18 | City |
| Melissa | 10 | 32,123 | 14,336 | 10.17% | 2,805 | 11 | City |
| Murphy | 11 | 21,122 | 21,082 | 0.03% | 3,708 | 6 | City |
| Josephine | 12 | 12,080 | 2,260 | 15.68% | 5,661 | 2 | City |
| Fairview | 13 | 11,169 | 10,427 | 1.12% | 1,259 | 9 | Town |
| Lavon | 14 | 10,464 | 4,544 | 10.41% | 2,438 | 4 | City |
| Lucas | 15 | 9,425 | 7,670 | 3.21% | 604 | 16 | City |
| Parker | 16 | 6,734 | 5,527 | 3.08% | 792 | 9 | City |
| Farmersville | 17 | 4,715 | 3,625 | 4.01% | 1,149 | 4 | City |
| Lowry Crossing | 18 | 2,197 | 1,689 | 4.02% | 847 | 3 | City |
| Nevada | 19 | 1,604 | 1,324 | 3.02% | 672 | 2 | City |
| Blue Ridge | 20 | 1,281 | 1,181 | 1.34% | 1,089 | 1 | City |
| Weston | 21 | 1,254 | 282 | 14.84% | 279 | 4 | City |
| St. Paul | 22 | 1,007 | 991 | 0.3% | 702 | 1 | Town |
| New Hope | 23 | 693 | 665 | 0.73% | 483 | 1 | Town |
| Union Valley | 24 | 577 | 378 | 6.07% | 218 | 3 | City |
| Hebron | 25 | 218 | 221 | 0% | 813 | 0 | Town |
| Mobile City | 26 | 183 | 140 | 3.98% | 12,200 | 0 | City |
Plano is the largest city in Collin County, with a population of 296,718.
Mobile City is the smallest city in Collin County, with a population of 183.
There are 26 cities in Collin County, Texas.