20 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Ontwa township | 1 | 6,836 | 6,898 | -0.03% | 352 | 19.42 | Township |
| Howard township | 2 | 6,239 | 6,257 | -0.21% | 181 | 34.53 | Township |
| Dowagiac | 3 | 5,646 | 5,713 | -0.23% | 1,268 | 4.45 | City |
| Porter township | 4 | 3,940 | 3,754 | 0.23% | 76 | 51.52 | Township |
| LaGrange township | 5 | 3,741 | 3,782 | -0.16% | 113 | 33.19 | Township |
| Milton township | 6 | 3,251 | 3,132 | 1.06% | 154 | 21.11 | Township |
| Silver Creek township | 7 | 3,041 | 3,056 | 0.16% | 95 | 31.96 | Township |
| Union township | 8 | 2,829 | 2,955 | -1.57% | 80 | 35.47 | Township |
| Jefferson township | 9 | 2,581 | 2,589 | 0.12% | 74 | 34.74 | Township |
| Marcellus township | 10 | 2,457 | 2,401 | 0.49% | 74 | 33.20 | Township |
| Pokagon township | 11 | 2,077 | 2,114 | -0.19% | 61 | 34 | Township |
| Calvin township | 12 | 2,034 | 1,996 | 0.84% | 59 | 34.35 | Township |
| Penn township | 13 | 1,767 | 1,755 | 0.28% | 53 | 33.61 | Township |
| Cassopolis | 14 | 1,706 | 1,736 | -0.35% | 848 | 2.01 | Village |
| Newberg township | 15 | 1,601 | 1,607 | 0.06% | 46 | 34.51 | Township |
| Edwardsburg | 16 | 1,277 | 1,309 | -0.47% | 1,397 | 0.91 | Village |
| Volinia township | 17 | 1,151 | 1,091 | 1.59% | 33 | 34.39 | Township |
| Marcellus | 18 | 1,035 | 1,070 | -0.67% | 1,518 | 0.68 | Village |
| Union township | 19 | 479 | 471 | 0.42% | 13 | 35.81 | Township |
| Vandalia | 20 | 321 | 331 | -0.62% | 325 | 0.99 | Village |
Ontwa township is the largest city in Cass County, with a population of 6,836.
Vandalia is the smallest city in Cass County.
There are 20 cities in Cass County, Michigan.