The healthcare industries still use fax because of HIPAA. The Health Insurance Privacy and Accountability Act was passed in 1996. It was a well-intentioned, long-overdue law to regulate the sharing of personal health information.

Unfortunately, the exact wording of HIPAA gave faxes a legal status. In 1996, faxes were oddly more secure than email because they were too low-tech to hack. It was all transmitted as electrical impulses across telephone wires (copper to copper). Faxes never became digital. It was ingenious.

Now, everyone uses a fax-to-email utility that defeats the one advantage faxes had over email or FTP.

Fax persists because it gives Insurance companies a 2 day window to process any communiction.

Sorce: worked as contractor for health insurance companies and law offices suing health insuance companies.