How to fax from a computer, and receive faxes without a machine

What you need to send a fax

Every fax has the same four parts, however you send it:

1. The document, as a file. A PDF is the safest choice. If the paper original is all you have, scan it or photograph it flat in good light.
2. The recipient's fax number, with the area code. In the US and Canada that is 10 digits.
3. A cover sheet, if the recipient expects one. It says who the fax is for, who sent it and how many pages follow. Our fax cover sheet guide has free templates.
4. A way to send it. That is the choice below.

Three ways to fax from a computer

Online fax is the only one of the three that needs no phone line. It is also the only one that needs no machine of your own, switched on and connected, for faxes to arrive.

Online fax, step by step

1. Sign in to your online fax service in a web browser or its app.
2. Start a new fax and enter the recipient's fax number.
3. Upload the document. Add a cover page if you need one.
4. Send it, and wait for the confirmation.

The service dials the recipient's machine and delivers the pages. Incoming faxes work the other way round: the service answers your fax number and puts each fax in an inbox as a document.

A multifunction printer, from the print dialog

If your printer can fax, your computer can send a fax through it. On a Mac, Apple's guide has you open the document and choose File > Print. Choose your printer from the list under Faxes, type the fax number in Recipients, and click Fax. You can add a cover page in the same dialog. On Windows, the printer maker's software does the same job.

The printer still needs its own phone line. Faxes you receive usually print on paper.

Windows Fax and Scan

Windows Fax and Scan is included in some editions of Windows. To turn it on, open Control Panel > Programs and Features > Turn Windows features on or off, and tick Windows Fax and Scan under Print and Document Services. If it is not in the list, your edition does not support it. Microsoft says it is not available on Arm-based Windows PCs.

It sends and receives through a fax modem connected to a phone line, or through a fax server on your network. It receives only while the computer is on and connected.

How to receive a fax without a fax machine

To receive faxes without a machine, you need a fax number that delivers to an inbox instead of a printer. You have two ways to get one:

• A new fax number from an online fax service. Give it to the people who send you faxes.
• Your existing number, moved. If your fax number is printed on forms and letterhead, ask the online fax service to port it. Keep your old service running until the move is complete, so faxes keep arriving.

Once the number is in place, each fax arrives as a document. You can open it, save it to a client or patient file, forward it, or print it if you need paper.

Fax machines on a VoIP phone line

Offices that move their phones to the internet often find the fax machine stops working. A fax machine sends each page as a stream of modem tones, and VoIP carries sound as packets of data that can garble those tones. A standard called T.38 carries fax over the internet more reliably. It only works when the fax equipment and the provider on each internet leg of the call support it.

Online fax sidesteps the problem. It sends and receives documents, not tones, so there is no machine on the line to fail.

Getting a fax through the first time

• Send a PDF. It keeps the layout. Filled-in form fields can be lost when some tools flatten a file, so check the preview before you send.
• Keep the file small. Very large scans are slow, and some services limit upload size. A clear black-and-white scan at normal resolution is enough.
• Dial the full number. Include the area code, and check it against the recipient's letterhead or website.
• Keep the confirmation. It is your proof the fax was delivered, and when.

How this works on PBXflex

PBXflex includes online fax on every plan, in the same app as your calls and texts. A fax extension gives you a fax number and a shared fax inbox, in the web app.

• To send, upload the document to the fax inbox and send it. Uploads can be up to 8 MB, and pages are sized automatically, so fewer are rejected by the receiving machine.
• Every fax you send produces a PDF delivery confirmation for the file. A failed fax retries automatically.
• Filled PDF form fields and comments survive the send, so nobody has to print and rescan a form.
• Incoming faxes arrive as documents in a shared inbox. When the sender is in your contacts, the fax shows their name. It is marked read once someone opens it.
• Separate inboxes and folders keep referrals, records and engagement letters apart.
• A fax page uses 2 credits, sent or received, from the same balance as your calls and texts.

Porting is free on every plan. The switching guide explains how moving a number works. If you want texting and fax but are keeping your current phone system, see Text & Fax.