Area Code 231-331 located in ALDEN, ANTRIM, MI, more detail is as below. Place NPA (Numbering Plan Area) : 231 NXX (Local Number Prefix) : 331 City : ALDEN County : ANTRIM State : MI (Michigan) NXX Use Type : Landline NXX Intro Version : 1999-07-22 FIPS (Federal Information Processing Standards) : 26009 LATA (Local Access Transport Area) : 348 Rate Center : ALDEN ZIP Code Count : 446 ZIP Code Frequency : 46 ZIP Code : 49612 Other Information NPANXX : 231331 County Population : 0 Switch CLLI (Common Language Location Identifier) : ALDNMIXHRS0 Time Zone : Eastern (GMT -05:00) Observes Daylight Saving Time : Yes Company : FRONTIER NORTH, INC. - MI OCN (Operating Company Number) : 0695 Coverage Area Name : ALDEN Latitude : 44.8835 Longitude : -85.2773 ‹ previous : 231-330 next › : 231-331 Telephone Number List 231-331-0000 ~ 231-331-9999