Note: As defined by the US Census Bureau, a city's official boundaries often extend miles beyond the city itself and may even cross county lines. As such, several thousand US cities officially exist in two or more counties (and therefore appear on multiple counties' lists of cities.)
City | Rank | 2024 Pop. | 2020 Pop. | Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Lexington township | 1 | 3,453 | 3,462 | -0.17% | 96 | 36.0 | Township |
| Worth township | 2 | 3,446 | 3,468 | -0.29% | 89 | 38.6 | Township |
| Sandusky | 3 | 2,679 | 2,703 | -0.22% | 1,248 | 2.1 | City |
| Croswell | 4 | 2,290 | 2,312 | -0.26% | 972 | 2.4 | City |
| Sanilac township | 5 | 2,290 | 2,293 | -0.13% | 56 | 40.8 | Township |
| Marlette | 6 | 1,852 | 1,855 | -0.05% | 1,147 | 1.6 | City |
| Marlette township | 7 | 1,666 | 1,681 | -0.36% | 32 | 52.5 | Township |
| Elk township | 8 | 1,495 | 1,512 | -0.53% | 42 | 35.7 | Township |
| Speaker township | 9 | 1,336 | 1,344 | -0.3% | 39 | 34.6 | Township |
| Brown City | 10 | 1,292 | 1,302 | -0.23% | 1,139 | 1.1 | City |
| Watertown township | 11 | 1,244 | 1,251 | -0.24% | 35 | 35.1 | Township |
| Maple Valley township | 12 | 1,164 | 1,175 | -0.43% | 34 | 34.5 | Township |
| Buel township | 13 | 1,162 | 1,161 | -0.09% | 31 | 37.6 | Township |
| Moore township | 14 | 1,091 | 1,104 | -0.46% | 30 | 36.3 | Township |
| Lexington | 15 | 929 | 919 | 0.22% | 672 | 1.4 | Village |
| Deckerville | 16 | 876 | 883 | -0.23% | 702 | 1.2 | Village |
| Peck | 17 | 596 | 602 | -0.33% | 573 | 1.0 | Village |
| Port Sanilac | 18 | 566 | 570 | -0.18% | 665 | 0.9 | Village |
| Carsonville | 19 | 499 | 502 | -0.2% | 431 | 1.2 | Village |
| Applegate | 20 | 224 | 227 | -0.44% | 223 | 1.0 | Village |
| Minden City | 21 | 182 | 182 | 0% | 185 | 1.0 | Village |
| Melvin | 22 | 151 | 154 | -0.66% | 156 | 1.0 | Village |
| Forestville | 23 | 84 | 86 | -1.18% | 106 | 0.8 | Village |
Note: City markers shown outside the county boundary mean that a part of the city extends into this county, but is primarily located in an adjacent county.
Lexington township is the largest city in Sanilac County.
Forestville is the smallest city in Sanilac County.
There are 23 cities in Sanilac County, Michigan.