Tutanota

Tutanota is one of the most popular email providers to be chosen by the privacy enthusiasts. However, similar to ProtonMail, they do not respect open standards and appears to block VPN/TOR registrations.

Others

 * 1) Tutanota does not support mail clients but rather only their webmail. Their webmail lacks support for OpenPGP encryption. Instead, they uses their own flawed encryption - which they could easily insert a backdoor and gets all your mail contents.
 * 2) Though the service is free, if you want to pay for a better service, it does not accept crypto payments.