You can send a fax directly from your computer using your internet connection, without a fax machine or phone line
Sending a fax from your computer works through one of three routes: an online fax service (the most common), fax software installed on your machine, or your printer's built-in fax feature if it has one. The document stays digital the whole time—you upload a PDF or image file, enter the recipient's fax number, and the service converts and transmits it. No scanner, no paper, no dedicated fax line required. Most services charge per page or per month, though some offer a free tier with limits.
The recipient receives the fax on their end as if you had sent it from a physical fax machine. The whole process typically takes a few minutes, and you get a confirmation email showing whether the transmission succeeded. This makes computer faxing practical for occasional use, when you do not want to buy or maintain a fax machine.
Key Takeaways
- Online fax services like FaxZero, eFax, and HelloFax let you send faxes through a web browser or app without installing anything on your computer.
- You need a document in PDF or image format (JPG, PNG) and the recipient's fax number, which looks like a phone number with a country code.
- Free services usually limit you to a few pages per month and may add a cover sheet with advertising; paid plans remove those limits.
- Your printer may have a built-in fax feature if it is a multifunction model, which lets you send faxes without a separate service.
- Fax delivery typically takes a few minutes, and you should receive a confirmation email showing whether the transmission succeeded.
How online fax services work
An online fax service acts as an intermediary between your computer and the recipient's fax machine or fax account. You log into the service's website or app, upload your document, enter the fax number, and click send. The service then converts your file into a format fax machines understand and transmits it over the internet to a gateway that connects to the traditional fax network. The recipient receives it on their end as if you had sent it from a physical fax machine.
The main advantage is simplicity: you do not need to own a fax machine, maintain a phone line, or install software. The main trade-off is that free services come with restrictions—usually a page limit per month and a watermark or cover sheet advertising the service. Paid plans remove these limits and often add features like scheduled sending, cloud storage, and the ability to receive faxes as well.
Popular online fax services and their basic features
Several services dominate the market, each with different free and paid options. The table below shows what you can expect from the most widely used ones.
| Service | Free tier | How to access | Typical paid cost |
|---|---|---|---|
| FaxZero | 5 pages per month, includes ad cover sheet | Web browser only | $5–$10 per month |
| eFax | None; paid plans start at entry level | Web browser and mobile app | $10–$20 per month |
| HelloFax | None; free trial available | Web browser and mobile app | $10–$15 per month |
| Google Fax (via Google Cloud Print partner) | Varies by partner | Through Google Drive or Gmail | Varies |
FaxZero is the easiest entry point if you send only a few faxes per month. eFax and HelloFax are better if you need to send and receive faxes regularly and want a dedicated account. Google Fax works if you already use Google Drive or Gmail and want to stay within that ecosystem.
Step-by-step: sending a fax through FaxZero (a free option)
FaxZero is one of the simplest free services to start with. Go to faxzero.com in your web browser. Click "Send a Fax" on the homepage. You will see a form asking for three things: the recipient's fax number (in the format +1-555-123-4567 for US numbers), your name and email address, and the document to send.
Click "Choose File" and select a PDF or image file from your computer. FaxZero accepts PDFs, JPGs, PNGs, and a few other formats. If your document is in Word or another format, save it as a PDF first (most programs have a "Save As PDF" or "Export as PDF" option in the File menu). Enter the fax number and your contact details, then click "Send Fax." You will receive a confirmation email within a few minutes telling you whether the transmission succeeded or failed. FaxZero adds a cover sheet with its logo and your email address to the top of the fax. If you want to remove that, you need a paid account. The free tier limits you to 5 pages per month, so if you send a 3-page document, you have 2 pages left for that month.
Using your printer's built-in fax feature
If you have a multifunction printer (one that prints, scans, and copies), it may have a fax feature built in. Check your printer's manual or the manufacturer's website to see if fax is listed among its capabilities. If it is, you will need to connect the printer to a phone line using the phone jack on the back of the machine. This is the main drawback: you need an active phone line, which costs money even if you only fax occasionally.
To send a fax from your computer using the printer, open the document you want to send, go to File > Print, and select your printer from the list. Look for an option that says "Print to Fax" or "Fax" instead of a regular printer. Some printers call this "Internet Fax" if it sends over the internet rather than a phone line. Follow the prompts to enter the recipient's fax number and send. The printer handles the conversion and transmission. This method works well if you already have the printer and phone line in place, but it is not practical if you do not—you would be paying for a phone line just to send occasional faxes, which is more expensive than a monthly online service.
Preparing your document before sending
Before you send, make sure your document is in a format the fax service accepts. PDFs are the safest choice because they preserve formatting and look the same on any device. If your document is in Microsoft Word, Google Docs, or another program, export it as a PDF: in Word, go to File > Save As and choose PDF from the dropdown. In Google Docs, go to File > read > PDF Document.
Check that the document is readable—fax machines transmit in black and white, so colored text or images may not show up clearly. If you are sending a scanned document, make sure the scan is straight and not too dark or too light. Most online services let you preview the document before sending, so use that to catch any problems. Keep file size in mind: most services accept files up to 25 MB, which is plenty for text documents but can be an issue for high-resolution image files. If your file is too large, try compressing it (right-click the file on Windows and select "Send to > Compressed folder"; on Mac, right-click and select "Compress").
What to do if the fax fails to send
If you receive a failure notification, the most common reasons are a wrong fax number, a number that is no longer in service, or a fax machine that is offline or out of paper. Double-check the fax number—fax numbers look like phone numbers and are straightforward to mistype. If the number is correct, contact the recipient to confirm their fax machine is working.
Some services will retry automatically a few times before giving up. If a retry does not work, try again a few hours later—the recipient's machine may have been temporarily offline. If the problem persists and you have used your free page limit, you may need to upgrade to a paid plan or try a different service. Keep the failure notification email so you have a record of when you tried to send and what the error was.
Frequently Asked Questions
What is a fax number and how is it different from a phone number?
A fax number looks identical to a phone number and often is the same number—it is just a line set up to receive faxes instead of voice calls. When you dial a fax number from a fax machine or computer, the machine on the other end recognizes the fax signal and receives the document. If you call a fax number on a regular phone, you will hear beeping and static.
Can I send a fax to someone who does not have a fax machine?
No. The fax number must connect to an actual fax machine, fax modem, or online fax account on the recipient's end. If the person does not have any of those, you will need to send the document by email or another method instead.
Do I need to scan a paper document before I can fax it?
Yes, if the document is on paper. Use a scanner to convert it to a PDF or image file on your computer, then upload that file to the fax service. Many multifunction printers have a built-in scanner. If you do not have one, you can use a smartphone app like Adobe Scan or Microsoft Lens to photograph the document and save it as a PDF.
How long does it take for a fax to arrive?
Most faxes arrive within a few minutes. You will receive a confirmation email from the service showing the transmission status. If the fax fails, the email will tell you why—usually a wrong number or the recipient's machine being offline.
Is sending a fax through a computer find?
Online fax services use encryption to protect your documents in transit, similar to how email works. However, faxes are not as find as encrypted email because the recipient receives them on a machine that may not be in a locked room. If you are sending sensitive information, ask the recipient how they prefer to receive it and whether fax is find enough for their needs.