Area Code 406
Montana
Area code 406 serves Montana, primarily Billings, in the Mountain Time (MT) time zone. It has served the region since 01-Jan-1947.
Demographics
The estimated population served by area code 406 is approximately 1,616,483. The population density is 4 people per square mile, which is lower than the national average of 94. The median household income is $69,578, which is lower than the national median of $78,538. Approximately 32.2% of adults hold a bachelor's degree or higher, compared to the national rate of 35.0%. This rate is near the national average. The poverty rate stands at 12.6%, which is near the national rate of 12.4%.
History
Area code 406 is one of the original area codes established in 1947 when the North American Numbering Plan (NANP) was created.
Geographic Coverage
Area code 406 serves Montana, primarily the Billings area, in the Mountain Time (MT). It covers 497 communities. The geographic center of this area code is approximately 47.14°N, 110.91°W.
Demographics & Economics
- Total Population
- 1,616,483
- Population Density
- 4 people/sq mibelow U.S. average (U.S.: 94 people/sq mi)
- Median Household Income
- $69,578below U.S. median (U.S.: $78,538)
- Poverty Rate
- 12.6%near U.S. average (U.S.: 12.4%)
- Unemployment Rate
- 4.1%below U.S. average (U.S.: 5.2%)
- Education Attainment
- Bachelor's Degree+32.2%near U.S. average (U.S.: 35.0%)High School or Lower30.8%
Statistics are population-weighted aggregations from Census ACS 5-year estimates.See Sources for details.
Geographic Coverage
State
MT
Major Cities
- Billings
- Missoula
- Great Falls
- Bozeman
- Helena
- Kalispell
- Belgrade
- Helena Valley Southeast
- Anaconda-Deer Lodge County
- Havre
- Evergreen
- Livingston
- Whitefish
- Helena Valley West Central
- Lockwood
- Laurel
- Sidney
- Lewistown
- Four Corners
- Columbia Falls
- Polson
- Orchard Homes
- Bigfork
- Helena Valley Northwest
and 473 more cities
Time Zone
- Mountain Time (MT)
Current Time


County Coverage
Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 406).
| County | Population | Share |
|---|---|---|
| Yellowstone, MT | 172,237 | 10.7% |
| Missoula, MT | 128,360 | 7.9% |
| Gallatin, MT | 124,953 | 7.7% |
| Flathead, MT | 112,723 | 7.0% |
| Cascade, MT | 87,821 | 5.4% |
| Lewis and Clark, MT | 75,278 | 4.7% |
| Chouteau, MT | 72,048 | 4.5% |
| Jefferson, MT | 60,446 | 3.7% |
| Big Horn, MT | 60,353 | 3.7% |
| Park, MT | 56,698 | 3.5% |
| Deer Lodge, MT | 49,907 | 3.1% |
| Silver Bow, MT | 48,629 | 3.0% |
| Ravalli, MT | 46,715 | 2.9% |
| Lake, MT | 42,684 | 2.6% |
| Carbon, MT | 28,692 | 1.8% |
| Madison, MT | 24,841 | 1.5% |
| Prairie, MT | 21,522 | 1.3% |
| Hill, MT | 21,143 | 1.3% |
| Blaine, MT | 21,040 | 1.3% |
| Rosebud, MT | 20,978 | 1.3% |
| Lincoln, MT | 20,656 | 1.3% |
| Broadwater, MT | 20,542 | 1.3% |
| Richland, MT | 17,011 | 1.1% |
| Sanders, MT | 16,833 | 1.0% |
| Granite, MT | 14,655 | 0.9% |
| Powder River, MT | 14,483 | 0.9% |
| Glacier, MT | 14,390 | 0.9% |
| Teton, MT | 13,459 | 0.8% |
| Custer, MT | 13,401 | 0.8% |
| Valley, MT | 13,357 | 0.8% |
| Roosevelt, MT | 12,993 | 0.8% |
| Garfield, MT | 12,595 | 0.8% |
| Fergus, MT | 12,007 | 0.7% |
| Dawson, MT | 11,993 | 0.7% |
| McKenzie, ND | 10,722 | 0.7% |
| Stillwater, MT | 10,644 | 0.7% |
| Toole, MT | 10,180 | 0.6% |
| Beaverhead, MT | 10,096 | 0.6% |
| McCone, MT | 9,739 | 0.6% |
| Powell, MT | 8,819 | 0.5% |
| Idaho, ID | 6,579 | 0.4% |
| Pondera, MT | 6,466 | 0.4% |
| Musselshell, MT | 5,903 | 0.4% |
| Mineral, MT | 5,795 | 0.4% |
| Phillips, MT | 5,433 | 0.3% |
| Petroleum, MT | 5,363 | 0.3% |
| Judith Basin, MT | 4,981 | 0.3% |
| Sheridan, MT | 4,382 | 0.3% |
| Fallon, MT | 4,248 | 0.3% |
| Sweet Grass, MT | 4,195 | 0.3% |
| Carter, MT | 3,917 | 0.2% |
| Meagher, MT | 2,883 | 0.2% |
| Wheatland, MT | 2,748 | 0.2% |
| Liberty, MT | 2,674 | 0.2% |
| Daniels, MT | 1,613 | 0.1% |
| Wibaux, MT | 1,164 | 0.1% |
| Golden Valley, MT | 1,031 | 0.1% |
| Treasure, MT | 898 | 0.1% |
| Divide, ND | 567 | 0.0% |
Call Context
This area code covers multiple cities and communities across a broad region in Montana. It is one of the original area codes established when the North American Numbering Plan was created in 1947.
Nearby Area Codes
Area codes geographically closest to 406.
Frequently Asked Questions
Common questions about area code 406 and how phone numbering works.
Phone numbers are assigned based on where the number was originally provisioned, not the caller's current location. Mobile phones retain their number when users move, and businesses may use numbers from regions where they don't have a physical presence. VoIP services can also provision numbers from virtually any area code.
Yes, mobile phones can have numbers from any area code in the region they were activated. Wireless carriers assign numbers from available pools regardless of phone type. When users change carriers or move to new areas, they typically keep their original number, which may have a different area code than their current location.
Start by looking up the area code on this site to understand its general geographic region. For the specific number, options include using your carrier's caller ID features or checking public directories. If you suspect fraud, you can report it to the FTC. To file a complaint about robocalls or spoofed numbers, visit the FCC Consumer Complaint Center. You can also register your number with the National Do Not Call Registry to reduce unwanted calls. Keep in mind that caller ID can display any name the caller chooses to set.
While Columbus is a prominent city in this area code's coverage, the code serves the broader surrounding region as well. Area codes are assigned geographically and typically cover multiple cities, towns, and communities beyond any single anchor city.
Yes, this is one of the original area codes established in 1947 when the North American Numbering Plan (NANP) was created. The initial set of area codes was designed to cover all of North America with a unified dialing system, and many of these original codes remain in use today, though some have been split or received overlays.
The estimated total population served by area code 406 is based on aggregated U.S. Census Bureau data for the counties within this area code. The population varies significantly between dense urban codes serving millions and rural codes covering smaller populations. You can find the specific population figure in the demographics section above.







