The Montana Area Code
Every active code: tap any card for its full guide, who called, cities and ZIPs, map, spam patterns and local time.
Got a call from a Montana number you don’t recognize?Open that code’s guide above for its full prefix lookup. AT&T ActiveArmor® blocks spam automatically, included with AT&T wireless plans.
- Fraud calls blocked automatically on the network
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- Reverse number lookup
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Included with AT&T wireless plans. Requires compatible device/service and download of the AT&T ActiveArmor® app. Other terms & restrictions apply. May not detect all threats and may block wanted calls. Some features require Advanced mobile security ($7/mo.). See terms.
See how ActiveArmor® worksIncluded with the free 30-day AT&T Wireless℠ trial- 100GB of data plus 25GB hotspot
- Unlimited talk & text in the U.S., Canada and Mexico
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Offer details
Service good for 30 days. Data: Limited to 100GB of data and 25GB of hotspot data. No additional data is available after limit is reached. Video is limited to SD quality. Talk & Text: Includes unlimited talk & text within the U.S. and unlimited text from the U.S. to over 230 countries. Limits: One trial per user. An unlocked, dual eSIM iPhone is required. You’ll receive a trial phone number that belongs to AT&T and is not available to be ported to another carrier or otherwise retained. Trial plan features and details may differ from or be unavailable in other AT&T plans. U.S. only. All terms subject to change at any time.
Montana Area Codes by City
The largest Montana communities and the area code that serve them. Every city links to its local AT&T internet page.
| City | Area code(s) |
|---|---|
| Billings | 406 |
| Great Falls | 406 |
| Missoula | 406 |
| Bozeman | 406 |
| Helena | 406 |
| Kalispell | 406 |
How Montana Got Its Codes
Every Montana area code, in the order it entered service. Splits carved new regions; added codes overlay existing ones, which is why ten-digit dialing is standard.
| In service | Code | How it arrived |
|---|---|---|
| 1947 | 406 | One of the original area codes of 1947 |
Source: NANPA NPA database, July 2026. Regenerated monthly.
Montana Area Code Map
Every active Montana area code at a glance, anchored to the metro each one serves. Tap any code above for its detailed coverage map.
Explore the interactive map
Click any region to open that area code's full guide. Hover for county names.
Open the printable Montana area code map (PDF) - poster format with a QR code back to this page.
Internet, wireless & stores across the state
AT&T Home Internet in Montana
AT&T home internet is available across Montana, checked address by address; every area code guide above lists its cities and what’s offered there.
AT&T Fiber: Ltd. avail/areas. Speeds based on wired connection. Actual speeds vary. For 5-GIG, single device wired speed maximum 4.7Gbps. For more info., visit att.com/speed101.
Start with home internet in Montana, or pair it with wireless in an internet + wireless bundle.
AT&T Wireless in Montana
AT&T’s 5G network covers most of Montana. ActiveArmor® spam blocking is included with every unlimited plan, your number stays yours when you move between Montana codes, and great cell phone deals in Montana are a tap away.
AT&T may temporarily slow data speeds if the network is busy. 5G req’s compatible plan & device. Coverage not available everywhere. Learn more at att.com/5Gforyou.
AT&T Stores Across Montana
From the Billings metro to Butte, Great Falls and beyond, walk in for switching, porting, upgrades and hands-on help. Every area code guide lists its nearest stores.
Find stores in: Billings · Butte · Great Falls · Bozeman · Missoula
