
Plainwell
- County:
- Allegan County
- County Seat:
- No
- Area (mi²):
- 2.075
- State:
- Michigan
Plainwell is a city located in Allegan County, Michigan. Plainwell has a 2025 population of 3,721. Plainwell is currently declining at a rate of -0.35% annually and its population has decreased by -1.72% since the most recent census, which recorded a population of 3,786 in 2020.
The average household income in Plainwell is $70,780 with a poverty rate of 11.7%. The median age in Plainwell is 39.9 years: 37.3 years for males, and 42.6 years for females.