There are four main reasons main reasons that fax is still used.
1) Because other people are using it
Fax still has a massive user base.
Just about every business has a fax machine and publishes their fax number publicly, as well some businesses insist on transmitting some of their data over fax.
Simply because it’s so prevalent, it’s still used so much.
2) In a lot of cases, it’s still quicker than other technology
Drop a piece of paper into the document feeder, press ten digits and a green button and your information is transmitted.
No need to scan to a computer, realize the document is upside down, then go back and re-scan it, go back to your computer, look up someone’s email address, and then send the document.
3) It’s an easy way to send signatures (as a bonus: without an image of those signatures touching a network)
It prints the document out automatically, where you can simply sign and initial it and fax it back to the other party.
Since a fax works over the phone line, there’s no need to worry about an image of a signature stored on a network.
4) Confirmation of document receipt and confirmation pages:
This reason is the biggest (rarely talked about) reason faxing is still in use.
When you send a fax, you can choose to receive a “confirmation page.” This is a printout that the fax machine on the receiving end has said: “message completely received.”
This is kind the electronic equivalent of sending registered mail – there is a record of the message being received by someone.
Other electronic methods (such as email, for example) are closer to regular mail – the message is sent, and there is no confirmation of its receipt.
The benefit to having a confirmation page is that it makes it more difficult for the other person to claim that they “never got the message.”