| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Opelousas | 1 | 14,962 | 15,767 | -0.9% | 1,547 | 10 | City |
| Eunice | 2 | 8,962 | 9,385 | -0.81% | 1,744 | 5 | City |
| Sunset | 3 | 3,240 | 2,976 | 1.44% | 1,004 | 3 | Town |
| Port Barre | 4 | 1,739 | 1,749 | -0.11% | 1,613 | 1 | Town |
| Arnaudville | 5 | 989 | 1,000 | -0.2% | 1,425 | 1 | Town |
| Krotz Springs | 6 | 872 | 900 | -0.57% | 505 | 2 | Town |
| Leonville | 7 | 870 | 869 | 0% | 319 | 3 | Town |
| Grand Coteau | 8 | 756 | 772 | -0.4% | 312 | 2 | Town |
| Melville | 9 | 730 | 757 | -0.68% | 581 | 1 | Town |
| Washington | 10 | 696 | 741 | -1.14% | 842 | 1 | Town |
| Cankton | 11 | 560 | 576 | -0.53% | 275 | 2 | Village |
| Palmetto | 12 | 94 | 94 | 0% | 106 | 1 | Village |
Opelousas is the largest city in St. Landry Parish, with a population of 14,962.
Palmetto is the smallest city in St. Landry Parish, with a population of 94.
There are 12 cities in St. Landry Parish, Louisiana.