18 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Bay City | 1 | 31,952 | 32,620 | -0.42% | 3,143 | 10 | City |
| Bangor charter | 2 | 13,845 | 14,030 | -0.07% | 981 | 14 | Township |
| Monitor charter | 3 | 10,630 | 10,679 | -0.04% | 289 | 37 | Township |
| Hampton charter | 4 | 9,616 | 9,679 | 0.06% | 350 | 27 | Township |
| Williams charter | 5 | 5,047 | 5,058 | 0.06% | 150 | 34 | Township |
| Kawkawlin | 6 | 4,386 | 4,416 | -0.05% | 135 | 32 | Township |
| Frankenlust | 7 | 3,708 | 3,670 | 0.27% | 176 | 21 | Township |
| Essexville | 8 | 3,284 | 3,372 | -0.55% | 2,536 | 1 | City |
| Portsmouth charter | 9 | 3,169 | 3,219 | -0.13% | 158 | 20 | Township |
| Beaver | 10 | 2,686 | 2,720 | -0.19% | 76 | 35 | Township |
| Pinconning | 11 | 2,288 | 2,299 | -0.09% | 62 | 37 | Township |
| Auburn | 12 | 2,041 | 2,065 | -0.24% | 1,933 | 1 | City |
| Garfield | 13 | 1,690 | 1,692 | 0.06% | 47 | 36 | Township |
| Zilwaukee | 14 | 1,483 | 1,531 | -0.67% | 671 | 2 | City |
| Mount Forest | 15 | 1,396 | 1,399 | -0.07% | 39 | 36 | Township |
| Pinconning | 16 | 1,181 | 1,201 | -0.34% | 1,372 | 1 | City |
| Gibson | 17 | 1,108 | 1,122 | -0.09% | 31 | 36 | Township |
| Bentley | 18 | 857 | 832 | 0.23% | 25 | 35 | Township |
Bay City is the largest city in Bay County, with a population of 31,952.
Bentley is the smallest city in Bay County, with a population of 857.
There are 18 cities in Bay County, Michigan.