18 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Sherman | 1 | 51,796 | 43,959 | 3.12% | 1,115 | 46 | City |
| Denison | 2 | 26,922 | 24,542 | 1.8% | 928 | 29 | City |
| Van Alstyne | 3 | 7,909 | 4,464 | 9.54% | 1,421 | 6 | City |
| Whitesboro | 4 | 4,160 | 4,082 | 0.36% | 1,245 | 3 | City |
| Howe | 5 | 3,678 | 3,622 | 0.3% | 737 | 5 | Town |
| Pottsboro | 6 | 2,851 | 2,495 | 2.55% | 904 | 3 | Town |
| Gunter | 7 | 2,603 | 2,078 | 4.2% | 134 | 19 | City |
| Preston | 8 | 2,202 | 1,759 | 0.32% | 438 | 5 | CDP |
| Collinsville | 9 | 2,086 | 1,878 | 2% | 2,111 | 1 | Town |
| Whitewright | 10 | 1,768 | 1,733 | 0.4% | 965 | 2 | Town |
| Bells | 11 | 1,519 | 1,521 | -0.07% | 716 | 2 | Town |
| Tioga | 12 | 1,319 | 1,163 | 2.41% | 670 | 2 | Town |
| Southmayd | 13 | 1,117 | 994 | 2.2% | 396 | 3 | City |
| Tom Bean | 14 | 957 | 920 | 0.74% | 661 | 1 | City |
| Knollwood | 15 | 817 | 765 | 1.24% | 2,514 | 0 | City |
| Sherwood Shores | 16 | 802 | 658 | -3.14% | 282 | 3 | CDP |
| Sadler | 17 | 364 | 371 | -0.55% | 344 | 1 | City |
| Dorchester | 18 | 103 | 95 | 0.98% | 69 | 1 | City |
Sherman is the largest city in Grayson County, with a population of 51,796.
Dorchester is the smallest city in Grayson County, with a population of 103.
There are 18 cities in Grayson County, Texas.