So which is more secure- an unencrypted email attachment or a client portal? Well, that is sort of a trick question because most everything is more secure than an unencrypted email attachment. And normally one would use the phrase "secure client portal" because by definition, client portals should be secure.
In this recent Oklahoma Bar Journal column, Email Attachments vs Client Portals, I discussed the differences between providing clients documents by sending them as email attachments versus providing the documents through a client portal. Some readers may be surprised at how easy and affordable providing a client portal is today. Some readers may have already used similar portals for a HIPAA-protected medical information provided by a health care provider.
Spoiler Alert: I think client portals are the best practice and unencrypted email attachments should be reserved for those situations where you would send a post card if you were using the U.S. Mail.