Mount Carroll
- County:
- Carroll County
- County Seat:
- Yes
- Area (mi²):
- 2.003
- State:
- Illinois
Mount Carroll is a city located in Carroll County, Illinois. Mount Carroll has a 2026 population of 1,433. It is also the county seat of Carroll County. Mount Carroll is currently declining at a rate of -0.56% annually and its population has decreased by -3.11% since the most recent census, which recorded a population of 1,479 in 2020.