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 |
|---|---|---|---|---|---|---|---|
| Sturgis | 1 | 10,972 | 11,132 | -0.36% | 1,614 | 6.8 | City |
| Three Rivers | 2 | 7,914 | 7,969 | -0.18% | 1,415 | 5.6 | City |
| Constantine township | 3 | 4,035 | 4,046 | 0.05% | 117 | 34.5 | Township |
| White Pigeon township | 4 | 3,792 | 3,761 | 0.32% | 151 | 25.1 | Township |
| Lockport township | 5 | 3,788 | 3,742 | 0.58% | 133 | 28.5 | Township |
| Nottawa township | 6 | 3,744 | 3,688 | 0.48% | 105 | 35.6 | Township |
| Sherman township | 7 | 3,454 | 3,443 | -0.12% | 105 | 33.0 | Township |
| Colon township | 8 | 3,345 | 3,329 | 0.39% | 97 | 34.4 | Township |
| Fabius township | 9 | 3,317 | 3,311 | 0.03% | 104 | 32.0 | Township |
| Burr Oak township | 10 | 2,654 | 2,632 | 0.49% | 75 | 35.3 | Township |
| Mendon township | 11 | 2,596 | 2,577 | 0.39% | 74 | 34.9 | Township |
| Park township | 12 | 2,382 | 2,395 | 0% | 68 | 34.9 | Township |
| Nottawa township | 13 | 2,197 | 2,181 | -0.18% | 62 | 35.3 | Township |
| Sturgis township | 14 | 2,023 | 2,040 | -0.15% | 116 | 17.4 | Township |
| Constantine | 15 | 1,989 | 1,993 | -0.05% | 1,216 | 1.6 | Village |
| White Pigeon | 16 | 1,723 | 1,731 | -0.12% | 1,223 | 1.4 | Village |
| Flowerfield township | 17 | 1,612 | 1,592 | 0.19% | 45 | 35.5 | Township |
| Fawn River township | 18 | 1,526 | 1,535 | -0.07% | 80 | 19.1 | Township |
| Mottville township | 19 | 1,455 | 1,445 | 0.21% | 75 | 19.3 | Township |
| Centreville | 20 | 1,320 | 1,323 | -0.08% | 891 | 1.5 | Village |
| Colon | 21 | 1,193 | 1,212 | -0.42% | 868 | 1.4 | Village |
| Leonidas township | 22 | 1,159 | 1,157 | 0.09% | 33 | 35.5 | Township |
| Florence township | 23 | 1,148 | 1,147 | 0.18% | 35 | 33.2 | Township |
| Mendon | 24 | 863 | 882 | -0.58% | 882 | 1.0 | Village |
| Burr Oak | 25 | 755 | 774 | -0.66% | 750 | 1.0 | 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.
Sturgis is the largest city in St. Joseph County.
Burr Oak is the smallest city in St. Joseph County.
There are 25 cities in St. Joseph County, Michigan.