Area Code 406-225 located in BOULDER, JEFFERSON, MT, more detail is as below. Place NPA (Numbering Plan Area) : 406 NXX (Local Number Prefix) : 225 City : BOULDER County : JEFFERSON State : MT (Montana) NXX Use Type : Landline NXX Intro Version : 1994-02-04 FIPS (Federal Information Processing Standards) : 30043 LATA (Local Access Transport Area) : 648 Rate Center : BOULDER ZIP Code Count : 603 ZIP Code Frequency : 76 ZIP Code : 59632 Other Information NPANXX : 406225 Switch CLLI (Common Language Location Identifier) : BLDRMTMARS1 MSA CBSA (Core Based Statistical Area) : Helena, MT MSA CBSA Code (Core Based Statistical Area) : 25740 Time Zone : Mountain (GMT -07:00) Observes Daylight Saving Time : Yes Company : QWEST CORPORATION OCN (Operating Company Number) : 9636 Coverage Area Name : BOULDER Latitude : 46.2353 Longitude : -112.1155 ‹ previous : 406-225 next › : 406-226 Telephone Number List 406-225-0000 ~ 406-225-9999