Proton’s mails are encrypted… between proton accounts. Send an email to a hotmail account and bye-bye encryption. Proton does rely on PGP so you can use that if the recipient supports it.
A Password-protected Email is an email that requires a password to open it. It’s a way you can send a secure, end-to-end encrypted email to anyone who isn’t on Proton Mail.
Proton’s mails are encrypted… between proton accounts. Send an email to a hotmail account and bye-bye encryption. Proton does rely on PGP so you can use that if the recipient supports it.
Mail stored in proton is encrypted
https://proton.me/support/password-protected-emails