| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hammond | 1 | 75,276 | 77,760 | -0.58% | 3,310 | 23 | City |
| Gary | 2 | 66,934 | 68,976 | -0.53% | 1,341 | 50 | City |
| Merrillville | 3 | 37,534 | 36,462 | 0.34% | 1,130 | 33 | Town |
| Crown Point | 4 | 35,880 | 33,994 | 0.74% | 1,887 | 19 | City |
| Schererville | 5 | 29,846 | 29,666 | 0.07% | 1,975 | 15 | Town |
| Hobart | 6 | 29,210 | 29,725 | -0.3% | 1,115 | 26 | City |
| St. John | 7 | 25,761 | 20,494 | 3.7% | 1,980 | 13 | Town |
| East Chicago | 8 | 25,457 | 26,346 | -0.6% | 1,804 | 14 | City |
| Munster | 9 | 23,425 | 23,888 | -0.34% | 3,108 | 8 | Town |
| Highland | 10 | 23,289 | 23,963 | -0.51% | 3,363 | 7 | Town |
| Cedar Lake | 11 | 17,339 | 14,204 | 3.28% | 1,835 | 9 | Town |
| Dyer | 12 | 16,218 | 16,491 | -0.34% | 2,635 | 6 | Town |
| Griffith | 13 | 16,052 | 16,539 | -0.53% | 2,066 | 8 | Town |
| Lake Station | 14 | 12,916 | 13,259 | -0.47% | 1,557 | 8 | City |
| Lowell | 15 | 12,035 | 10,700 | 1.54% | 1,714 | 7 | Town |
| Winfield | 16 | 9,458 | 7,236 | 3.48% | 763 | 12 | Town |
| Whiting | 17 | 4,459 | 4,572 | -0.45% | 2,468 | 2 | City |
| New Chicago | 18 | 1,982 | 2,008 | -0.3% | 2,945 | 1 | Town |
| Schneider | 19 | 259 | 269 | -0.77% | 301 | 1 | Town |
Hammond is the largest city in Lake County, with a population of 75,276.
Schneider is the smallest city in Lake County, with a population of 259.
There are 19 cities in Lake County, Indiana.