| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Sealy | 1 | 8,139 | 6,822 | 2.55% | 694 | 12 | City |
| Bellville | 2 | 4,404 | 4,208 | 0.57% | 1,617 | 3 | City |
| Wallis | 3 | 1,390 | 1,298 | 1.31% | 930 | 1 | City |
| San Felipe | 4 | 750 | 689 | 1.49% | 90 | 8 | Town |
| Brazos Country | 5 | 540 | 514 | 0.56% | 276 | 2 | City |
| Industry | 6 | 304 | 267 | 2.01% | 285 | 1 | City |
| South Frydek | 7 | 241 | 216 | 1.69% | 136 | 2 | City |
Sealy is the largest city in Austin County, with a population of 8,139.
South Frydek is the smallest city in Austin County, with a population of 241.
There are 7 cities in Austin County, Texas.