The three ways to fax from your computer

You can fax a document from your computer in three ways: through an online fax service, through your printer if it has fax capability, or through fax software on your computer. The easiest route depends on whether you already have the right hardware and how often you need to fax.

Online fax services are the most straightforward if you don't have a fax machine or fax-capable printer. You upload your document, enter the recipient's fax number, and the service sends it. Printer-based faxing works if your multifunction printer has a fax modem built in. Fax software lets you send directly from your computer but requires either a fax modem or a connection to an online service.

Each method has different costs and setup steps. Most people find online fax services simplest because they require no hardware beyond what you already have — a computer and internet connection.

Key Takeaways

  • Online fax services like FaxZero, eFax, and HelloFax let you send faxes through a web browser without owning a fax machine.
  • If your printer is a multifunction device with a fax modem, you can fax directly from your computer through the printer's software.
  • Some online services offer free faxing with limits (usually 3 to 5 pages per day), while others charge monthly or per-fax fees.
  • You need the recipient's fax number, not their phone number, and the document must be in a format your chosen method accepts (PDF, image, or Word document).

Using an online fax service

Online fax services are the most common choice because they work on any computer with internet access and require no special hardware. Popular services include FaxZero, eFax, HelloFax, and Fax.plus. Each has a slightly different interface, but the basic steps are the same: create an account, upload your document, enter the fax number, and send.

FaxZero is free for up to 5 pages per fax, up to 3 faxes per day, with a cover page included. You don't need to create an account for a single fax — you can send as a guest. eFax charges a monthly subscription (around $10 to $20 depending on the plan) but includes a dedicated fax number so people can fax you back. HelloFax offers a free tier with limits and paid plans starting around $10 per month.

To send a fax through FaxZero: go to faxzero.com, click "Send a Fax", upload your PDF or image file, enter the recipient's fax number, add your name and email, and click send. The fax arrives within minutes. If you use a paid service like eFax, you log into your account, click "Send Fax", upload the document, enter the number, and send the same way.

Faxing through a multifunction printer

If you own a multifunction printer — the kind that prints, scans, and copies — it may have fax capability built in. Check your printer's manual or the manufacturer's website to confirm. Common brands with fax-capable models include HP, Canon, Brother, and Xerox, though not every model has this feature.

To fax through your printer, your computer must be connected to the printer (either by USB or network), and the printer must be connected to a phone line. This is the main limitation: you need an active landline or a VoIP service that supports faxing. If you have neither, this method won't work.

Once your printer is set up and connected to a phone line, open the document you want to fax on your computer. Go to File > Print, select your printer from the list, then look for a "Fax" or "Send as Fax" option in the printer settings. Click it, enter the recipient's fax number, and send. The exact steps vary by printer model, so check your printer's manual if you don't see a fax option.

Using fax software on your computer

Fax software like Windows Fax and Scan (built into Windows) or third-party programs like MetroFax lets you send faxes directly from your computer. Windows Fax and Scan is free and comes with Windows 10 and Windows 11. On a Mac, you can fax through the Print dialog in most applications.

To use Windows Fax and Scan, open the application, click "New Fax", and compose your fax. You can add a cover page, attach documents, and enter the recipient's fax number. When you click send, the software routes the fax through your fax modem (if you have one) or through an online service it connects to.

The catch is that Windows Fax and Scan works best if you have a fax modem installed in your computer — a piece of hardware that handles the fax transmission. Most modern computers don't come with fax modems. If you don't have one, the software can still work by connecting to an online fax service, but you're essentially using the online service anyway, so using the service directly is simpler.

What format your document needs to be in

Most fax services accept PDF files, image files (JPG, PNG, TIFF), and sometimes Word documents or other office formats. PDF is the safest choice because it preserves formatting and works with every service.

If you have a paper document, scan it to PDF first. Most printers with scanning capability can do this — place the document on the scanner, open the printer's software on your computer, and select "Scan to PDF". If your printer doesn't have scanning, use a smartphone app like Adobe Scan or Microsoft Lens to photograph the document and save it as a PDF.

If your document is in Word or another format, save it as a PDF before uploading to a fax service. In Word, go to File > Save As, choose PDF from the file type dropdown, and save. This ensures the formatting stays correct when the fax service processes it.

Finding the correct fax number

A fax number looks like a phone number but is not the same thing. Calling a fax number on a regular phone produces noise and doesn't connect you to a person. The recipient must give you their fax number specifically — it's usually listed on their business card, website, or letterhead.

If you're not sure whether a number is a fax number, ask the person or organization directly. Some businesses have a single number that handles both voice calls and faxes, but this is less common. Government offices, law firms, and medical practices almost always have a dedicated fax number.

Enter the fax number exactly as the recipient provides it, including any area code or country code. If you're faxing internationally, you may need to add a plus sign and the country code (for example, +44 for the United Kingdom).

Costs and limits to know about

Free online fax services have restrictions. FaxZero limits you to 3 faxes per day and 5 pages per fax. Some services limit you to a certain number of faxes per month. If you fax regularly, a paid service is more practical.

Paid services typically charge a monthly subscription ($10 to $25) that includes a set number of faxes per month, or they charge per fax (usually $1 to $3). Some services charge for incoming faxes if you want a dedicated fax number. Compare what you actually need — if you send one fax every few months, a free service is fine. If you send multiple faxes per week, a monthly plan saves money.

Using a printer's fax capability costs only what you pay for your phone line or VoIP service, but remember that you need an active landline or compatible VoIP service, which many people no longer have.

Frequently Asked Questions

Can I fax to a cell phone number?

No. Faxes go only to fax machines or fax-capable devices like multifunction printers. Cell phones cannot receive faxes. If someone gives you only a cell phone number, ask them for their fax number or an email address instead.

What if the fax doesn't go through?

Check that the fax number is correct and that the recipient's fax machine is turned on and connected to a phone line. If you're using an online service, check your account for a delivery confirmation or error message. Most services show whether a fax was sent successfully. If it failed, try again or contact the recipient to confirm their fax number.

Do I need to include a cover page?

No, but it's helpful. A cover page includes your name, phone number, the date, and the number of pages, so the recipient knows who sent the fax and how many pages to expect. Most online fax services include a cover page automatically, but you can usually turn it off if you don't want one.

Can I fax from my phone?

Yes, through an online fax service. Download the service's app (eFax, HelloFax, and others have mobile apps), upload your document from your phone's camera or files, and send the same way you would from a computer. The process is nearly identical.

Is faxing secure?

Faxing is less secure than email or encrypted messaging. Faxes sent over phone lines can theoretically be intercepted, and faxes received on a shared machine can be read by anyone nearby. If you're sending sensitive information like medical records or financial documents, confirm with the recipient that they want it by fax and that they have a secure way to receive it.