Area Code 231-238 located in CHEBOYGAN, CHEBOYGAN, MI, more detail is as below. Place NPA (Numbering Plan Area) : 231 NXX (Local Number Prefix) : 238 City : CHEBOYGAN County : CHEBOYGAN State : MI (Michigan) NXX Use Type : Landline NXX Intro Version : 1999-07-22 FIPS (Federal Information Processing Standards) : 26031 LATA (Local Access Transport Area) : 348 Rate Center : INDIAN RIV ZIP Code Count : 245 ZIP Code Frequency : 7 ZIP Code : 49721 Other Information NPANXX : 231238 County Population : 0 Switch CLLI (Common Language Location Identifier) : INRVMIMNRSA Time Zone : Eastern (GMT -05:00) Observes Daylight Saving Time : Yes Company : AMERITECH MICHIGAN OCN (Operating Company Number) : 9323 Coverage Area Name : INDIAN RIVER Latitude : 45.4108 Longitude : -84.6127 ‹ previous : 231-237 next › : 231-238 Telephone Number List 231-238-0000 ~ 231-238-9999