| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Lockhart | 1 | 18,904 | 14,374 | 4.1% | 1,159 | 16 | City |
| Luling | 2 | 5,977 | 5,600 | 0.96% | 1,085 | 6 | City |
| Uhland | 3 | 2,034 | 1,588 | 3.88% | 533 | 4 | City |
| Martindale | 4 | 1,305 | 1,243 | 0.54% | 633 | 2 | City |
| Niederwald | 5 | 1,178 | 674 | 0.86% | 321 | 4 | City |
| Mustang Ridge | 6 | 1,040 | 958 | 1.46% | 279 | 4 | City |
| Mountain City | 7 | 686 | 636 | 1.63% | 1,304 | 1 | City |
| Creedmoor | 8 | 394 | 436 | -1.99% | 52 | 8 | City |
| Hays | 9 | 279 | 231 | 2.95% | 1,251 | 0 | City |
Lockhart is the largest city in Caldwell County, with a population of 18,904.
Hays is the smallest city in Caldwell County, with a population of 279.
There are 9 cities in Caldwell County, Texas.