Here is the comparison list I was mentioning earlier, pseudo-Wirecutter-style:
Criteria
- English
- Free tier without third-party invitation requirements and/or a trial period
- No advertisements
- No email address and/or phone number requirements for signup and/or service usage
Picks
- Autistici/Inventati
- MsgSafe.io (Acquisition Transition)
- Skiff (Imminent Shutdown)
- Tuta
Competition
- AOL Mail
- cock.li
- CounterMail
- Criptext
- CTemplar
- Cyberfear
- Disroot
- Fastmail
- Gmail
- GMX
- HEY
- Hushmail
- iCloud
- Kolab Now
- Librem Mail
- Lycos Mail
- mailbox.org
- mail.com
- Mailfence
- Mailo
- Mail.ru
- Outlook
- Posteo
- PrivateMail
- Proton Mail
- Rackspace Email
- Rediffmail
- Riseup
- RMail
- Runbox
- SecureMyEmail
- ServerMX
- Soverin
- StartMail
- Thexyz
- Unseen
- VFEmail
- Webmail.co.za
- Yahoo Mail
- Yandex Mail
- Zoho Mail