ProtonMail - Secure email with absolutely no compromises. Get your free encrypted email account today.
Skizzle Email - Skizzle is the most secure way to share end-to-end encrypted files through email, backed by blockchain
Tutanota - Get your encrypted mailbox for free.
mailbox.org - mailbox.org offers a secure e-mail account for home and business use. The domain name, me@mailbox.
Kleopatra - Kleopatra is a certificate manager and GUI for GnuPG.
ElectronMail - Unofficial desktop app for ProtonMail and Tutanota end-to-end encrypted email providers