Canadian Number for a US Business: Cross-Border Guide

The short answer

A US business can have a Canadian phone number, and a Canadian business can have a US one. Both countries share one numbering plan and the +1 country code, so a Canadian number looks and dials like a US number. Most internet phone (VoIP) providers that sell numbers in both countries let you pick an area code where your customers are, not where you sit.

Three things do not cross the border easily:

• Moving an existing number to a provider in the other country. Porting is tied to the number's home area, and carriers generally support only their own country's numbers.
• Emergency calling. 911 (9-1-1 in Canada) follows the address registered with the provider, not the area code.
• The caller's cost. Whether a cross-border call is included or extra depends on the caller's plan.

Rules and provider policies below are as of October 2026. This is educational information, not legal or tax advice.

One numbering plan, two countries

Canada participates in the North American Numbering Plan (NANP), "the numbering plan used by the 20 nations sharing Country Code 1," and "shares the single digit Country Code '1' with 19 other nations," the United States among them ^[1]. A complete number is the country code 1 plus a 3-digit area code, a 3-digit central office code and a 4-digit line number.

CNAC's dial plan says long distance calls to NANP locations outside the caller's local area use 1 plus the 10-digit number, while calls outside Country Code 1 use an international prefix such as 011 ^[1]. A customer in Ohio dialling a Toronto number never dials 011.

Dialling and billing are separate questions. The numbering plan decides how a call is dialled; each carrier decides what it costs. Some plans include both countries, others charge a cross-border rate. Do not tell customers a call is free unless you know their plan.

Every number also has a fixed home area. The Canadian Numbering Administrator "assigns CO codes to Canadian Carriers in Exchange Areas" and keeps no list of individual numbers ^[2]. That home area is why porting across the border is hard (see below).

A Canadian number for a US business

Why a US business wants one:

• Canadian customers see a familiar area code and may be more likely to answer or call back.
• Canadian ads, listings and printed material can show a local-looking number.
• Some Canadian callers may pay less to call a local Canadian number than a US one, depending on their plan.

How it works: you rent a number from a provider with Canadian inventory, and calls are delivered over the internet to wherever you answer. The FCC notes that "your VoIP provider may permit you to select an area code for your VoIP service that is different from the area code in which you live" ^[3]. That is what lets a Seattle office answer a Vancouver 604 number.

Choosing the area code. Pick the city where most of your Canadian callers are. Where an area has run short of numbers, a new code is often added on top of the old one (an overlay): both codes serve the same area, new numbers come from the new code, and 10-digit dialling is generally required ^[2]. Either code reads as local there. More on caller reactions: our business phone number area code guide.

Ask the provider before buying:

1. Does it sell numbers in that Canadian city, and can it port Canadian numbers in later?
2. Does it require a Canadian address for this number type? Requirements vary by provider.
3. Can calls ring phones in the US without extra per-minute charges?

A US number for a Canadian business

The same logic runs the other way. A Montreal or Calgary firm selling into the US can rent a number in a US area code where its customers are and answer it from Canada; the FCC's area-code point applies to any VoIP provider selling US numbers ^[3].

Points that matter more on this side:

• Pick a real market: the metro area of your largest US customer group, not a random code.
• Watch callbacks: if staff call US customers back from Canadian mobiles, customers see a Canadian number and may not answer. Say on your greeting which number you call back from.
• Check the address rule: a Canadian service address on a US number is common for VoIP, but confirm the provider allows it.

Porting across the border: why it usually fails

Porting keeps a number while changing providers. The FCC's wording is the key: "If you're switching service providers and remaining in the same geographic area, you can keep your existing phone number," but "if you are moving to a new geographic area, you may not be able to keep your current phone number" ^[4].

A number does not change country when it changes provider, and the receiving provider must support its home area. One carrier help page states that a number's rate center "stays the same" across providers, that "US and Canadian carriers only support numbers within their country," and that "cross-country portability is usually not supported" ^[5]. That is a provider's description, not a regulation, but it is consistent with the FCC's geographic rule and with how porting is run: Canada has its own porting database, which the CRTC describes as storing "routing information for all telephone numbers in Canada" ^[6]. No FCC or CRTC rule we found provides for porting a number between the two countries.

The workable path: a provider that supports numbers in both countries, so each number stays in its own country's system while your staff are wherever they are.

What porting providers ask for. Twilio's published guidelines show the difference:

• Canada: a Letter of Authorization (LOA) dated within the last 30 days, the most recent bill, the account number and PIN if required, and an LOA showing "your actual Canadian service address" that matches the current carrier's records. Twilio quotes 5-7 working days and says a port is rejected if you do not answer the losing provider's approval text within 90 minutes ^[7].
• US: an LOA, name and address matching the Customer Service Record (CSR), a bill dated within 30 days, account number and PIN if required. Twilio quotes 5 to 15 days for standard ports, up to 4 weeks or longer, and names incorrect name or address as the most common rejection reason ^[8].

These are one provider's quotes, not regulatory deadlines; see how long number porting takes.

Pitfalls:

• Putting your US office address on a Canadian port. It must match the losing carrier's (Canadian) record.
• Cancelling the old service first. The FCC says not to terminate it before starting with the new company ^[4].
• Assuming a mobile number can go anywhere. A Canadian mobile number still has a Canadian home area.

Toll-free: one number for both countries

Toll-free is the number type not tied to a city. CNAC lists 800, 888, 877, 866, 855, 844 and 833 as toll-free codes in service in Canada's dial plan ^[1], the same codes the FCC lists for the US ^[9]. Somos, which administers the toll-free database, says more than 42 million toll-free numbers are in use "throughout the U.S., Canada and parts of the Caribbean" ^[10].

From the FCC guide:

• The codes "are not interchangeable": 1-800 and 1-888 versions of the same digits reach different subscribers. Print the exact number.
• "Wireless callers, however, will be charged for the airtime minutes used during a toll free call unless they have an 'unlimited calling' plan."
• Toll-free numbers are portable to a new provider (a "RespOrg").

Toll-free suits a website serving both countries, but it looks national, not local. Many cross-border firms pair it with a local number in each main market. Before buying, confirm in writing that the number accepts calls from both US and Canadian callers. More: toll-free numbers.

911 and your registered location

An area code says nothing about where your staff are. Emergency calling follows the physical address your provider has on file.

United States. The FCC requires interconnected VoIP providers to obtain "a customer's physical location prior to service activation," offer easy ways to update it, and send 911 calls with a callback number and the registered location. It warns that VoIP 911 calls "may not connect to the 911 call center serving your current location" ^[11].

Canada. The CRTC's framework for local VoIP is Telecom Decision CRTC 2005-21 (4 April 2005). Its 9-1-1 duties are about routing "a 9-1-1 call originating from a local VoIP service" to the right emergency centre (paras. 52 and 68), plus telling customers about the service's 9-1-1 limitations (paras. 93-94) ^[12]. Telecom Circular CRTC 2008-2 (28 July 2008) summarizes how this works for nomadic service: providers cannot automatically detect whether you are at your registered address, so a 9-1-1 call goes first to a call centre that verbally confirms your location, and the registered address is used only when that fails ^[13]. Canada is also moving to next-generation 9-1-1; as of October 2026 the CRTC's date for retiring the legacy 9-1-1 network is 31 March 2027 ^[14].

For a cross-border team:

• A Canadian number answered in the US (or the reverse) has the 911 behaviour of the service and address behind it, not of its area code.
• A line that only receives and forwards calls cannot place a call, so it cannot originate a 911 or 9-1-1 call. The duties above attach to services that place calls; the US definition of interconnected VoIP requires the ability to both receive calls from and make calls to the phone network ^[15]. Emergency calls go out on the phone that dials them, under that phone's registered address, so everyone needs a phone that can dial 911. This is general information, not legal advice.
• Staff working from two addresses should keep each registered address current.

Taxes, records and legal address

• A phone number in a country is not, by itself, a business registration, tax registration or legal address there.
• Whether selling into the other country creates tax or registration obligations is a question for an accountant who works in both countries.
• Use the same business name on the phone account, the LOA and your public listings; name and address mismatches are a common port rejection reason.

Cross-border setup checklist

Numbers

• List where your callers are, by city.
• Choose: a local number per market, toll-free, or both.
• Confirm the provider sells numbers in both countries.
• If porting, get the account number, PIN, and the exact name and service address on the account.
• Keep the old service active until the port is confirmed complete.

Routing

• Decide who answers each market's calls; write menu options around what callers need ("For orders, press 1").
• Set business hours per line if staff are in different time zones, and state them in the closed message.
• Offer French for Quebec callers where it fits.
• Test from a mobile in each country: ringing, voicemail, caller ID.

Safety and records

• Registered address current on any service that can dial 911 / 9-1-1.
• Phone invoices filed with your cross-border records.
• Numbers written as +1 NXX NXX-XXXX on international material.

FAQ

Can I move my Canadian number to a US provider? Only if that provider supports Canadian numbers in the number's area; a US-only carrier usually cannot take it ^[5]. Ask the provider to check the exact number first.

Do US customers pay long distance to call my Canadian number? They dial 1 + 10 digits, not 011 ^[1]. Any charge depends on their plan. Toll-free avoids a charge for landline callers; mobile callers may still use airtime ^[9].

Do I need a Canadian office to have a Canadian number? No regulator page we checked requires one for a new VoIP number, but provider rules vary. For a port, the LOA must show the Canadian service address on the current account ^[7].

Auto Attendant offers US and Canadian numbers with a simple caller menu at $29 USD per line per month.