Area Code 406: Billings, Montana
406 is a telephone area code serving Montana, including Billings, Helena. It is part of the North American Numbering Plan and is dialed with the country code +1.
Numbers beginning with 406 are located in Montana, United States (NANP region: Statewide). The code covers Billings, Helena.
How to Dial Area Code 406
| Calling from | What to dial |
|---|---|
| Anywhere in the US or Canada | 1 406 XXX-XXXX (10-digit dialing: 406 + 7-digit number) |
| Local call inside the same area code | 7-digit number in most areas; 10 digits where an overlay code is active |
| From the UK or Europe | 00 1 406 XXX XXXX |
| From Australia | 0011 1 406 XXX XXXX |
| From a mobile phone anywhere | +1 406 XXX XXXX |
Whatever country you are calling from, the + symbol replaces the exit code. Save the contact as +1 406 XXXXXXX and it will dial correctly from any phone in the world.
Time Zone for Area Code 406
Calls to a 406 number ring in the America/Denver time zone, standard offset UTC-07:00. Daylight saving time applies here, so the offset moves forward one hour from March to November.
Cities and Communities Served by 406
The following places fall inside the 406 calling area:
Other Area Codes in Montana
These codes also serve Montana. Area codes are assigned by the North American Numbering Plan Administration (NANPA).
| Area Code | Cities / Coverage |
|---|
See all 1 area codes in Montana →
Frequently Asked Questions
Where is area code 406?
Area code 406 is in Montana, United States. It covers Billings, Helena.
What time zone is area code 406 in?
Area code 406 rings in the America/Denver time zone (UTC-07:00 standard).
Do I need to dial 1 before area code 406?
Yes, for a long-distance call inside the US and Canada you dial 1 first, then 406, then the seven-digit number. The 1 is the North American long-distance trunk prefix — it is not the country code. From outside North America you dial your exit code then 1 then 406.
Is area code 406 toll-free?
No. 406 is a standard geographic area code, so normal long-distance rates apply unless your plan includes them. Toll-free NANP codes are 800, 833, 844, 855, 866, 877 and 888.