40 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Marion | 1 | 28,197 | 28,253 | -0.03% | 1,796 | 16 | City |
| Center | 2 | 21,720 | 21,617 | 0.25% | 870 | 25 | Township |
| Van Buren | 3 | 12,729 | 12,812 | -0.34% | 365 | 35 | Township |
| Mill | 4 | 10,414 | 10,444 | 0.07% | 449 | 23 | Township |
| Marion | 5 | 8,993 | 8,822 | 0.54% | 136 | 66 | Township |
| Pleasant | 6 | 7,017 | 6,987 | 0.29% | 201 | 35 | Township |
| Marion | 7 | 6,499 | 6,669 | -0.75% | 124 | 53 | Township |
| Gas City | 8 | 6,068 | 6,137 | -0.18% | 1,207 | 5 | City |
| Jefferson | 9 | 5,705 | 5,670 | 0.25% | 137 | 42 | Township |
| Van Buren | 10 | 4,350 | 4,317 | 0.35% | 123 | 35 | Township |
| Van Buren | 11 | 4,313 | 4,227 | 0.33% | 115 | 38 | Township |
| Marion | 12 | 4,126 | 3,845 | 1.3% | 119 | 35 | Township |
| Fairmount | 13 | 3,994 | 3,964 | 0.33% | 131 | 30 | Township |
| Upland | 14 | 3,821 | 3,815 | 0.03% | 1,218 | 3 | Town |
| Van Buren | 15 | 3,175 | 3,202 | -0.19% | 99 | 32 | Township |
| Van Buren | 16 | 2,979 | 2,909 | 1.09% | 79 | 37 | Township |
| Van Buren | 17 | 2,773 | 2,799 | -0.18% | 92 | 30 | Township |
| Fairmount | 18 | 2,661 | 2,676 | -0.08% | 1,678 | 2 | Town |
| Marion | 19 | 2,013 | 1,909 | 0.8% | 59 | 34 | Township |
| Marion | 20 | 1,959 | 1,928 | 0.67% | 79 | 25 | Township |
| Van Buren | 21 | 1,940 | 1,918 | -0.15% | 22 | 87 | Township |
| Van Buren | 22 | 1,855 | 1,777 | 1.03% | 74 | 25 | Township |
| Van Buren | 23 | 1,787 | 1,785 | 0.17% | 50 | 35 | Township |
| Marion | 24 | 1,714 | 1,696 | 0.47% | 31 | 55 | Township |
| Sims | 25 | 1,677 | 1,678 | 0.24% | 70 | 24 | Township |
| Marion | 26 | 1,560 | 1,498 | 0.45% | 41 | 39 | Township |
| Jonesboro | 27 | 1,502 | 1,513 | -0.13% | 1,682 | 1 | City |
| Van Buren | 28 | 1,455 | 1,453 | 0.48% | 52 | 28 | Township |
| Marion | 29 | 1,391 | 1,457 | -1.07% | 44 | 32 | Township |
| Marion | 30 | 1,288 | 1,240 | 1.1% | 28 | 46 | Township |
| Marion | 31 | 1,103 | 1,109 | -0.09% | 33 | 33 | Township |
| Sweetser | 32 | 1,072 | 1,071 | 0% | 1,063 | 1 | Town |
| Marion | 33 | 934 | 910 | 0.21% | 26 | 36 | Township |
| Swayzee | 34 | 901 | 913 | -0.22% | 1,921 | 0 | Town |
| Van Buren | 35 | 834 | 839 | 0% | 23 | 36 | Township |
| Van Buren | 36 | 786 | 785 | 0% | 1,348 | 1 | Town |
| Marion | 37 | 686 | 686 | 0.15% | 19 | 35 | Township |
| Matthews | 38 | 486 | 482 | 0.21% | 1,381 | 0 | Town |
| Green | 39 | 452 | 453 | 0.22% | 16 | 28 | Township |
| Fowlerton | 40 | 274 | 270 | 0.37% | 1,398 | 0 | Town |
Marion is the largest city in Grant County, with a population of 28,197.
Fowlerton is the smallest city in Grant County, with a population of 274.
There are 40 cities in Grant County, Indiana.