Founded in 1829, Eaton County is one of 83 counties in the state of Michigan. Historically, Eaton County was formed from unorganized territory. The city of Charlotte is the county seat. With FIPS code of 45, Eaton County has a population of 108,944 and area of 579 square miles (1,500 km2).
List of all cities in Eaton County, MI alphabetically
| City/Town | Postal Code | Area Code |
| Bellevue, MI | 49021 | 269 |
| Charlotte, MI | 48813 | 517 |
| Dimondale, MI | 48821 | 517 |
| Eaton Rapids, MI | 48827 | 517 |
| Grand Ledge, MI | 48837 | 517 |
| Lansing, MI | 48908 | 517 |
| 48917 | 517 | |
| Mulliken, MI | 48861 | 517 |
| Olivet, MI | 49076 | 269 |
| Potterville, MI | 48876 | 517 |
| Sunfield, MI | 48890 | 517 |
| Vermontville, MI | 49096 | 517 |