Area Code 406-635 located in MILES CITY, CUSTER, MT, more detail is as below. Place NPA (Numbering Plan Area) : 406 NXX (Local Number Prefix) : 635 City : MILES CITY County : CUSTER State : MT (Montana) NXX Use Type : Landline NXX Intro Version : 1997-10-11 FIPS (Federal Information Processing Standards) : 30017 LATA (Local Access Transport Area) : 650 Rate Center : TERRY ZIP Code Count : 29 ZIP Code Frequency : 7 ZIP Code : 59301 Other Information NPANXX : 406635 Switch CLLI (Common Language Location Identifier) : TRRYMTAARS0 Time Zone : Mountain (GMT -07:00) Observes Daylight Saving Time : Yes Company : MID-RIVERS TELEPHONE COOPERATIVE, INC. OCN (Operating Company Number) : 2246 Coverage Area Name : FALLON Latitude : 46.7926 Longitude : -105.3125 ‹ previous : 406-634 next › : 406-635 Telephone Number List 406-635-0000 ~ 406-635-9999