I've used both for some time and decided to move to Fastmail and so far I am very satisfied. Fastmail does one thing and does it well, email. There is no PGP s

I've used both for some time and decided to move to Fastmail and so far I am very satisfied. Fastmail does one thing and does it well, email. There is no PGP support. Protonmail does PGP in the browser via a library that they serve you themselves which I find less than ideal. If you want to do it outside the browser you need to have a subscription and download a bridge software that needs to be running on your machine. With Fastmail if I need PGP in my email I do it via the GPGTools plugin for the Mail app which uses the system gpg installation.