State directory / Montana
US number directory / Montana
Montana
area codes
NANPA records 1 active geographic area code for Montana, including 406 from 1947.
1geographic area code
in this reference
in this reference
Earliest listed406 · 1947
Standard timeMT
Overlays in this stateNone recorded in this snapshot
Major city starting points
Helena (capital): 406; Billings (largest city in state reference): 406.
| City | Reference role | Codes to check |
|---|---|---|
| Helena | Capital | 406 |
| Billings | Largest city in state reference | 406 |
City reference · 2026-10-25
Codes, cities & coverage
NANPA lists no active overlay complex for Montana on 2026-10-25.
| Code | Region / major cities named in the reference | Introduced | Active overlay complexes |
|---|---|---|---|
| 406 | Montana (all) | 01-Jan-1947 | None active in NANPA snapshot |
NANPA dates & overlays · 2026-10-25
Wikipedia geography · 2026-10-25 · CC BY-SA 4.0
Time zones
Montana spans 1 standard-time offset in the state reference: MT.
| Standard offset | Region | Daylight saving |
|---|---|---|
| UTC−07:00 MT | Mountain | Yes |