Area code 406

Where area code 406 is

406 is one of 1 geographic area codes serving Montana; NANPA records its in-service date as January 1, 1947. It is not part of an overlay, so every number in its territory starts with 406. It is in the Mountain time zone. The places with the most assigned exchanges include Billings, Missoula, Helena, Great Falls, and Bozeman. By population, its largest named places are Billings, Missoula, Great Falls, Bozeman, and Helena.

Where 406 numbers are local

406 holds 100% of the 754 central office codes assigned in Montana, the most of any code in the state. 117 Census places could be matched to rate centers with 406 exchanges; the most populous are Billings (121,000), Missoula (78,204), Great Falls (60,013), and Bozeman (57,894). For a storefront or service area inside 406, the place pages show which prefixes are rated local there.

How calls are dialed in 406

According to NANPA's dialing-plan data, local calls within 406 are dialed as ten digits (area code plus number) and toll calls as 1 plus ten digits. Ten-digit local dialing means the area code is part of how customers save and recognize your number, so print it in full everywhere. NANPA's dialing-plan note for this code reads: "1+10 digit permissible at service provider discretion."

Phone companies in area code 406

63 carriers hold the 754 central office codes assigned in 406. Qwest Corporation has the most, with 132 (18%). 527 of the codes (70%) are pooled, meaning the code holder shares blocks of 1,000 numbers with other carriers instead of using all 10,000 itself. Numbers can move between carriers through porting, so a code's holder tells you where the block started, not where every number lives now.

Where 406 numbers are rated

NANPA assigns each central office code to a rate center, the local calling area that decides whether a call is local or toll. 406 has codes in 260 rate centers. The table lists the rate centers with the most codes, with the matching Census place where the abbreviation could be matched.

406 code assignments over time

An area code has 800 possible central office codes that start with 2 through 9, a few of which are reserved (such as N11 service codes and 555). 754 are assigned in 406, 94% of 800. 30 were assigned in 2020 or later.

Getting a 406 number for your business

Callata Office costs $99 per month for up to 5 people, and each additional user is $20 a month. That covers up to 3 local numbers, calling from a browser or your cell, transcribed voicemail, recorded calls with AI summaries, after-hours routing and E911 on each number.

If you already have a number in area code 406, porting it to Callata is free. Texting from a local number requires a one-time carrier registration (10DLC, $49), and the numbers available in any area code depend on carrier inventory when you choose them.

Optional AI agents (receptionist, sales, support or scheduler) can answer calls after hours or when nobody picks up, take messages, text, email and transfer to your team. They are billed from prepaid AI minutes at $0.25 per minute, identify themselves as AI, and may only place outbound calls to people who consented, between 8am and 9pm.