Area Code +1-406-(4400000...4409999) located in Helena, Montana (MT), more detail is as below. Place International Dialing Code : 1 International Prefix : 011 National Prefix : 1 National Destination Code : 406 Subscriber Number From : 4400000 Subscriber Number To : 4409999 National Destination Code Length : 3 Uses National Destination Code : Yes National Significant Number Length : 10 Number Type : G (Geographic Land Line, Fixed Line) Carrier Name : 3 RVRS TEL COOP MT Click here to buy United States Area Code Database Other Information Language Code : en (English) Country Number : 840 (United States) Country Code : US (United States) Region Code : MT Region Name : Montana City : Helena Timezone : America/Denver Coordinated Universal Time : -07:00 Daylight Saving Time : Yes National Significant Number Minimum Length : 10 Latitude : 46.6000 Longitude : -112.0200 ‹ previous : +1-406-(4399000...4399999) next › : +1-406-(4410000...4419999) Dialling Instructions For trunk calls: 0 406 4400000 (Trunk Code + National Destination Code + Subscriber Number) For international calls: 011 1 406 4400000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number) Telephone Number List 4400000 ~ 4409999 (Count: 10,000) Example: +1-406-4400000 / 0111-406-4400000 (1406-4400000 / 1-406-4400000) +1-406-4400001 / 0111-406-4400001 (1406-4400001 / 1-406-4400001) +1-406-4400002 / 0111-406-4400002 (1406-4400002 / 1-406-4400002) +1-406-4400003 / 0111-406-4400003 (1406-4400003 / 1-406-4400003) +1-406-4400004 / 0111-406-4400004 (1406-4400004 / 1-406-4400004) ...+1-406-xxxxxxx / 0111-406-xxxxxxx (1406-xxxxxxx / 1-406-xxxxxxx) ...+1-406-4409995 / 0111-406-4409995 (1406-4409995 / 1-406-4409995) +1-406-4409996 / 0111-406-4409996 (1406-4409996 / 1-406-4409996) +1-406-4409997 / 0111-406-4409997 (1406-4409997 / 1-406-4409997) +1-406-4409998 / 0111-406-4409998 (1406-4409998 / 1-406-4409998) +1-406-4409999 / 0111-406-4409999 (1406-4409999 / 1-406-4409999)