Area Code 406-637 located in TERRY, PRAIRIE, MT, more detail is as below. Place NPA (Numbering Plan Area) : 406 NXX (Local Number Prefix) : 637 City : TERRY County : PRAIRIE State : MT (Montana) NXX Use Type : Landline NXX Intro Version : 1994-02-04 FIPS (Federal Information Processing Standards) : 30079 LATA (Local Access Transport Area) : 650 Rate Center : TERRY ZIP Code Count : 51 ZIP Code Frequency : 100 ZIP Code : 59349 Other Information NPANXX : 406637 Switch CLLI (Common Language Location Identifier) : TRRYMTMARS1 Time Zone : Mountain (GMT -07:00) Observes Daylight Saving Time : Yes Company : QWEST CORPORATION OCN (Operating Company Number) : 9636 Coverage Area Name : FALLON Latitude : 46.7926 Longitude : -105.3125 ‹ previous : 406-636 next › : 406-638 Telephone Number List 406-637-0000 ~ 406-637-9999