Summary
Fax numbers function almost exactly like phone numbers, using country codes, area codes, and local digits to direct documents where you want them to go. Their length varies by region, and international faxing is just as easy as local faxing, as long as you have the right dialing prefix and country code. With a basic understanding of fax number structure, sending your documents through FaxBurner’s online service means you don’t even have to leave your house to do it.
Fax Number Example and Format – How Long Is a Fax Number?
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4-5 minutes |
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Even in a world full of email, Google Drive, cloud storage, and digital signatures, faxing still has a place. This is especially true for businesses, vendors, and organizations that rely on consistent document delivery.
If you’ve ever been asked to send a fax and wondered, “wait a minute, what is a fax number?”, or how long it’s supposed to be, or how it differs from a regular phone number, you’re not alone.
Understanding how fax numbers work makes sending and receiving faxes far easier, whether you’re using traditional equipment or a modern online fax tool like FaxBurner. In this article, you’ll find everything you ever wanted to know (and probably some things you didn’t) about fax number formats, how they’re structured, and why they still matter today.
What is a Fax Number?
A fax number is the unique identifier that tells a fax network where to deliver a document. It works much like a phone number, but instead of connecting two people by voice, it connects two fax endpoints, whether digital or physical.
A fax number allows you to:
- Send faxes: The sending device “dials” the recipient’s fax number to reach the correct machine or service.
- Receive faxes: The fax network uses the number to route incoming documents to the right inbox, device, or digital dashboard.
Fax numbers are essential for accurately directing documents, much like an email address, except they’re formatted like a phone number.
Phone Numbers vs. Fax Numbers
Fax numbers and phone numbers look nearly identical, so how do you tell them apart?
Legacy fax machines rely on telephone lines to transmit documents, whereas online faxing uses the internet. That’s why you can’t tell them apart just by looking at them. The difference lies in how each system handles the call behind the scenes.
- A phone number is meant to connect voice calls, so dialing one makes the device of the person you’re calling ring.
- Since a fax number is meant to send or receive fax transmissions, it produces fax tones when used. That’s why you hear those screeching noises if you ever dial a fax number by mistake.
You cannot distinguish a fax number from a phone number by looking at the digits alone. Sending and receiving your faxes online through an app like FaxBurner eliminates this confusion, meaning your phone number will never be confused for a fax number or vice versa, and is cheaper as well, along with numerous other benefits.
Fax Number Format Explained
Fax numbers follow the same structure as standard telephone numbering. The exact format depends on the country you’re sending to.
A typical fax number may include:
- Country code
- Area or region code
- Local number
- Optional extensions (less common for fax, but still something to watch out for)
For example:
U.S. fax number format:
+1 (555) 123-4567
UK fax number format:
+44 20 7123 4567
Regardless of the country, the underlying principle remains the same: the number identifies the destination fax endpoint.
How Long is a Fax Number?
The length of a fax number depends entirely on the country where you plan to send the fax, but in general, most countries have roughly the same number of digits in their fax numbers.
Here’s a quick breakdown:
- United States and Canada: 10 digits (not including the country code)
- Most of Europe: 9-12 digits
- Asia and Australia: 9-11 digits
- International dialing: Country codes typically add 1-3 additional digits. In the example above, the country code for the US is 1, whereas the country code for the UK is 44
Example lengths:
| Location | Typical Length | Example |
|---|---|---|
| United States | 10 digits | (776) 867-5309 |
| Canada | 10 digits | (416) 555-2368 |
| United Kingdom | 10-11 digits | 020 7946 0958 |
| Australia | 9 digits | (02) 9876 5432 |
| Japan | 9 digits | 03-1234-5678 |
Fax networks simply read the number as a destination, regardless of its total length, as long as the structure matches local dialing rules.
International Fax Numbers
When sending a fax internationally, you’ll use the same format you’d use when making an international call.
An international fax number will always include:
- Exit code (varies by country; in Canada and the US, it’s 011)
- Country code (1-3 digits)
- Area/region code
- Local number
Example: sending a fax from the US to the UK.
011 + 44 + 20 + 7123 4567
When calling the UK from abroad, you’ll dial +44 and drop the first zero from the country code, making it 20 instead of 020 as listed in the chart above.
Most digital services like FaxBurner simplify this by allowing you to enter the number in standard international format using the + symbol:
+ 44 + 20 + 7123 4567
This bypasses the need to dial exit codes manually.
Fax numbers may look just like traditional phone numbers, but they play a very specific role in routing documents quickly and accurately between businesses, partners, and organizations that still rely on faxing (yes, there are still quite a few!). Understanding how fax numbers work, their structure, purpose, and how they differ across regions, makes it easier to send or receive faxes without frustration.
And these days, you don’t even need a fax machine or dedicated fax line to participate. Faxburner allows you to send and receive everyday paperwork right from your smartphone, tablet, or computer. No matter what kind of documents you’re dealing with, mobile faxing gives you a simple, modern alternative to outdated hardware.
Once you understand fax number formats and how they function behind the scenes, you’ll be able to fax confidently from anywhere. If you’re ready to streamline the process even further, download the FaxBurner app and get your free temporary fax number right away.
Frequently Asked Questions
Do I need a fax number to send or receive a fax?
Yes, but with FaxBurner, you don’t need to set up a fax machine or dedicate a phone line.
Free accounts include a temporary fax number, and paid plans include a permanent one.
Can fax numbers be traced?
A fax number functions just like a phone number. It can be traced back to the owner or business, just like any other telephone line, depending on carrier records and public listings.
Where do I find the fax number on a fax machine?
The easiest place to find the fax number is on the device itself. Depending on the model, you may look:
- In the device’s settings menu
- On the first page of sent faxes (fax header)
- In the user manual or account settings (for digital fax services)
Can fax numbers include extensions?
The short answer is no… kind of. Fax machines and fax services rely on a direct, uninterrupted phone line to transmit. When you add an extension, the call typically has to pass through an automated phone menu (“Press 1 for…”) or a receptionist before reaching the right destination, something a fax cannot successfully navigate.
That said, there are rare exceptions:
- Some modern phone systems allow automatic extension dialing after a pause (e.g., 555-123-4567, 789) or after a series of asterisks that symbolize a one-second pause (e.g., +17783413020****5. This dials +17783413020, pauses for four seconds, and then dials the extension: 5.
- A few VoIP-based systems support automated routing directly to a fax line behind the scenes.
However, these setups are unreliable and not recommended, especially when it comes to sending important faxes. Fax transmissions need a stable, direct-to-line connection without menus, prompts, or call transfers.
Best practice: Use a dedicated fax number rather than an extension to ensure your fax reaches the correct destination without interruption.
Can a phone number also be a fax number?
Technically, yes. As long as the line connects to a fax machine. But if a voice call answers first or the line is shared, the fax may fail.
What happens if I fax the wrong number?
The fax will go to whichever endpoint the number belongs to. It’s very important to always double and triple-check before hitting send.
