Area Code 423-388 located in ERWIN, UNICOI, TN, more detail is as below. Place NPA (Numbering Plan Area) : 423 NXX (Local Number Prefix) : 388 City : ERWIN County : UNICOI State : TN (Tennessee) NXX Use Type : Wireless NXX Intro Version : 2002-08-04 FIPS (Federal Information Processing Standards) : 47171 LATA (Local Access Transport Area) : 956 Rate Center : ERWIN ZIP Code Count : 0 ZIP Code Frequency : Most frequently occurring ZIP Code, although percentage is unknown. ZIP Code : 37650 Other Information NPANXX : 423388 County Population : 0 Switch CLLI (Common Language Location Identifier) : JHCYTNXC8MD MSA CBSA (Core Based Statistical Area) : Johnson City, TN MSA CBSA Code (Core Based Statistical Area) : 27740 Time Zone : Eastern (GMT -05:00) Observes Daylight Saving Time : Yes Company : SPRINT SPECTRUM L.P. OCN (Operating Company Number) : 6664 Coverage Area Name : ERWIN Latitude : 36.1418 Longitude : -82.4146 ‹ previous : 423-387 next › : 423-389 Telephone Number List 423-388-0000 ~ 423-388-9999