| General Information about Area Code 231 | |
|---|---|
| Country | United States |
| State / Province / Territory | Michigan |
| Major City | Muskegon |
| Time Zone | Eastern (UTC-05:00) |
| Prefix | Primary City | County | Phone Type |
|---|---|---|---|
| 231-636 | Howard City | Montcalm | Landline |
| 231-871 | Beulah | Benzie | Landline |
| 231-220 | Muskegon | Muskegon | Landline |
| 231-223 | Kewadin | Antrim | Landline |
| 231-361 | Morley | Mecosta | Landline |
| 231-313 | Traverse City | Grand Traverse | Landline |
| 231-732 | Morley | Mecosta | Landline |
| 231-709 | Traverse City | Grand Traverse | Landline |
| 231-932 | Traverse City | Grand Traverse | Landline |
| 231-343 | Muskegon | Muskegon | Landline |
| 231-926 | Kalkaska | Kalkaska | Landline |
| 231-463 | Traverse City | Grand Traverse | Landline |
| 231-722 | Muskegon | Muskegon | Landline |
| 231-821 | Holton | Muskegon | Landline |
| 231-846 | Cadillac | Wexford | Landline |
| 231-745 | Baldwin | Lake | Landline |
| 231-792 | Mancelona | Antrim | Landline |
| 231-869 | Pentwater | Oceana | Landline |
| 231-760 | Muskegon | Muskegon | Landline |
| 231-755 | Muskegon | Muskegon | Landline |