| Area Code | 231 |
| State | Michigan |
| Current Time in Area Code 231 | 231> EDT |
| Timezone | Eastern Daylight Time |
| Regional Market Area | Grand Rapids-Kalamazoo-Battle Creek Area North Michigan Area |
| Metro Area(s) | Big Rapids, MI Cadillac, MI Ludington, MI Muskegon, MI Traverse City, MI |
| Population (2020) | 692595 |
| Adjacent Area Codes | 262,274,616,906,920,989 |