Where is the 406 area code?

Area code 406 covers Billings in Montana, on Mountain Time.

What time zone is area code 406 in?

Numbers in the 406 area code sit in Mountain Time.

Is 406 a toll-free or scam area code?

No. 406 is a geographic North American Numbering Plan area code assigned to Montana. Toll-free numbers use 800, 833, 844, 855, 866, 877 and 888. A call from 406 can still be spoofed, so treat unexpected calls with the usual caution.

Area code lookup

406 area code

Where the 406 area code is, which cities and counties it serves, the local time zone and the overlay codes dialled alongside it.

State: MT
Cities covered: 1
Counties: 1
Time zone: Mountain Time

Quick answer

Area code 406 serves Billings in Montana. It sits in Mountain Time and covers 1 county and about 4 ZIP codes across the metros we track.

Cities in the 406 area code

Each city links to its full local profile: sales tax, housing, income and ZIP codes.

City	County	Time zone	ZIP codes
Billings, MT	Yellowstone County	MST/MDT	4

406 area code FAQ

The questions people ask about this code.

Where is area code 406?

406 is a geographic area code in Montana, covering Billings.

What time is it in the 406 area code?

406 observes Mountain Time (MST/MDT).

Is 406 a scam area code?

No — it is a normal geographic code, not a toll-free or premium-rate prefix. Caller ID can be spoofed on any code, so verify unexpected callers before sharing information.

Sources & transparency

North American Numbering Plan Administrator (NANPA) area code assignments — area code to geography mapping and overlay relationships
US Census Bureau, American Community Survey 2019-2023 5-year estimates — city, county and ZIP code geography

Last reviewed August 2026. Figures are published for reference and can change; verify with the source agency before filing or contracting. How we build and check this data.