406 is an in-service United States area code assigned to Montana. It identifies a numbering region, not a caller’s current location.
NANPA assigns 406 to Montana. Montana’s Public Service Commission describes 406 as the statewide area code. Its numbering assignment does not identify a specific Montana city. Browse other codes in Montana
Additional area detail: Montana Public Service Commission.
View the official area-code maps ↗. Maps show numbering areas, not a caller’s location.
NANPA lists Mountain for this numbering area. These are numbering-region time zones, not a caller’s current location.
An area code can span more than one time zone. Local daylight-saving rules may differ.
Use the North American country calling code +1 followed by the three-digit area code and seven-digit local number. For example, write the pattern as +1 406 XXX XXXX. Local dialing rules and charges depend on your location and provider. Check a supported dialing format or check NANPA’s 10-digit dialing list.
NANPA’s US report listed 754 assigned prefixes on 2026-09-29. These are code assignments, not a count of active phone numbers or proof of a caller’s current carrier. Search any US area code and prefix.
| Rate center | Assigned prefixes |
|---|---|
| BILLINGS | 72 |
| MISSOULA | 47 |
| HELENA | 38 |
| GREATFALLS | 37 |
| BOZEMAN | 32 |
| Assignment company | Assigned prefixes |
|---|---|
| QWEST CORPORATION | 132 |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT | 119 |
| NEW CINGULAR WIRELESS PCS, LLC | 74 |
| ONVOY, LLC - MT | 43 |
| TRIANGLE TEL. COOP. ASSN., INC. | 39 |
754 assigned prefixes are listed for this area code. Search NANPA’s US central-office code assignments. The listed company and rate center describe an assignment; number portability means they cannot identify the current carrier, subscriber, or caller.
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Enter the full ten-digit number to see its structure and formatting. The check stays in your browser.
Enter a 10-digit +1 North American number. We check its structure and area-code record, not the caller’s identity or whether the line is active.
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The displayed number may be spoofed. Do not rely on an area code as proof of caller identity. If the caller claims to represent a business, end the call and contact that business using a number you found independently.
+1 406 is the statewide area code for Montana in the United States, not Canada. Established in 1947 as one of the original 86 area codes, it covers all of Montana.
406 is assigned to Montana, and the NANPA record associates it with Mountain time. A phone number does not reveal its owner’s current time zone. The clock above uses a representative time zone for the numbering area.
No. An area code is an assignment, and a person can travel, move, use internet calling, or display a spoofed number.
No. OfficialAreaCode has no live subscriber directory or spam-report database.