406 Area CodeBillings, MT
Area code 406 covers Billings and nearby communities in Montana, in the Mountain Time (MT) zone, home to about 773,000 people across 364 cities. It's the only area code for this region, so the three digits alone place the caller.
Overview
- Major City
- Billings
- State
- Montana (MT)
- Timezone
- Mountain Time (MT)
- Current Time
- Overlay
- No – unique area code
Where is area code 406?
Area code 406 serves part of Billings, MT and the surrounding areas. It is a unique area code with no overlays.
Overview of the 406 Area Code
What is the 406 area code?
The 406 area code serves Billings, Montana. When you see a 406 number, it indicates a local number within this geographic area.
Why was area code 406 created?
The 406 area code was established to serve the Billings region in Montana. It provides telephone number coverage across 364 cities.
Geographic Coverage of the 406 Area Code
The 406 area code serves Billings and surrounding areas in Montana. It operates within the Mountain Time (MT) time zone. This area code covers several key cities, including:
- Billings
- Missoula
- Great Falls
- Bozeman
- Helena
- Butte-Silver Bow
Got a call from a 406 number? It came from Billings, MT. No other area code overlaps the 406 territory, so the prefix alone identifies where the caller is. Inside 406, Billings holds about 16% of the population; the rest is split across 363 smaller cities.
Billings Area Code Overview
The 406 area code provides comprehensive telephone coverage for Billings and its surrounding communities. As the sole area code for this region, it uniquely identifies all local numbers within the service area.
What cities does area code 406 cover?
| City | State | Population | % of Area Code | % of City |
|---|---|---|---|---|
| Billings | MT | 121,483 | 0% | 100% |
| Missoula | MT | 78,204 | 0% | 100% |
| Great Falls | MT | 60,013 | 0% | 100% |
| Bozeman | MT | 57,894 | 0% | 100% |
| Helena | MT | 34,729 | 0% | 100% |
| Butte-Silver Bow | MT | 33,525 | 0% | 100% |
| Kalispell | MT | 31,296 | 0% | 100% |
| Belgrade | MT | 12,741 | 0% | 100% |
| Anaconda-Deer Lodge County | MT | 9,811 | 0% | 100% |
| Whitefish | MT | 9,256 | 0% | 100% |
* Sources: Population – U.S. Census Bureau PEP, Vintage 2024 (SUB-IP-EST2024-POP). Area code assignments – NANPA CO Code data. See our data methodology.
Has area code 406 been reported for unwanted calls?
Yes – 371 unwanted-call complaints were reported to the FTC for numbers showing a 406 area code (May 29 – Jul 2, 2026).
- 62% robocalls
- ↓ 10% vs prior period
Most-reported subjects
- Other47%175
- Reducing your debt (credit cards, mortgage, student loans)23%84
- Calls pretending to be government, businesses, or family and friends11%40
* Caller ID is easily spoofed, so these figures reflect the number shown on caller ID, not the caller's true location – an area code alone never identifies a caller. The FTC does not verify the facts in these complaints. Source: FTC Do Not Call (DNC) Reported Calls Data, retrieved 2026-07-05.
Which prefixes and exchanges belong to area code 406?
74% assigned to a telco
- 72% Landline
- 28% Wireless
- 0% Unknown
| Prefix | Usage | Carrier |
|---|---|---|
| (406)200- | Landline | Teleport Communications America Mt |
| (406)201- | Wireless | New Cingular Wireless Pcs |
| (406)202- | Wireless | New Cingular Wireless Pcs |
| (406)203- | Landline | Level 3 Communications |
| (406)204- | Landline | Level 3 Communications |
| (406)205- | Landline | Level 3 Communications |
| (406)206- | Landline | Level 3 Communications |
| (406)207- | Wireless | New Cingular Wireless Pcs |
| (406)208- | Wireless | New Cingular Wireless Pcs |
| (406)209- | Wireless | New Cingular Wireless Pcs |
Frequently Asked Questions about the 406 Area Code
Who called me from a 406 number?
A 406 number is assigned to Billings, Montana, so a call may come from there. But caller ID is easy to fake, and scammers often spoof a local 406 code to look nearby, so a 406 number doesn't prove the caller is local. Recently, 371 unwanted-call complaints were reported to the FTC for numbers showing the 406 code (62% flagged as robocalls). If you don't recognize the number, let it go to voicemail; a real caller will leave a message.
Is 406 a scam area code?
No area code is a scam on its own. 406 is a normal, officially assigned code for Billings, Montana. Spam callers spoof local codes to raise the odds you answer, so 406 on your caller ID says nothing about who is really calling. Recently, 371 unwanted-call complaints were reported to the FTC for numbers showing the 406 code (62% flagged as robocalls). Judge the call itself, not the area code.
Why do I keep getting calls from the 406 area code?
Repeated calls from different 406 numbers are usually spoofing: a robocaller rotates through 406 numbers so each call looks local and slips past simple blocks. Recently, 371 unwanted-call complaints were reported to the FTC for numbers showing the 406 code (62% flagged as robocalls). Blocking one number rarely helps; voicemail screening, your carrier spam filter, and the Do Not Call Registry work better.
Should I answer an unknown 406 number?
If you aren't expecting a 406 call, let it ring to voicemail. Legitimate callers leave a message, most robocallers hang up when no one picks up, and answering can mark your number as active and bring more calls.
How do I block calls from the 406 area code?
Block a single 406 number from your recent-calls list (iPhone: tap the number, then Block this Caller; Android: tap the number, then Block or report spam). To cut the volume, turn on Silence Unknown Callers on iPhone or spam protection on Android, enable spam filtering from your carrier, and register at DoNotCall.gov. Blocking the entire 406 code also stops legitimate local calls, so use it only as a last resort.
Where is area code 406?
Area code 406 covers Billings and the surrounding area in Montana, spanning 364 cities with about 772,848 residents. No other code overlays this region, so 406 alone identifies the area.
Is 406 a real area code?
Yes. 406 is an active code in the North American Numbering Plan, assigned by NANPA and in service for Billings, Montana. A real code can still show up on spoofed spam calls, so treat unknown 406 calls with normal caution.
What timezone is the 406 area code in?
The 406 area code is in the Mountain Time (MT). Because a number can be kept when someone moves or switches to VoIP, a specific 406 caller may not be in that zone.
How do I call a 406 number from abroad?
From outside the US, dial your country's exit code, then 1 (the US country code), then 406 and the seven-digit number. From a mobile phone you can usually just enter +1 406 followed by the number and let the phone add the exit code for you.