All email services in the world

What a massive task! Here's a list of popular email services in the world, grouped by category:

Web-based Email Services

  1. Gmail (Google)
  2. Yahoo Mail
  3. Outlook.com (Microsoft)
  4. AOL Mail
  5. ProtonMail (Swiss-based, end-to-end encrypted)
  6. Tutanota (German-based, end-to-end encrypted)
  7. Mail.ru (Russian-based)
  8. Yandex Mail (Russian-based)
  9. Zoho Mail
  10. FastMail (Australian-based)
  11. GMX Mail (German-based)
  12. 1&1 Mail (German-based)
  13. Mail.com (German-based)
  14. Lycos Mail (US-based)
  15. Juno Mail (US-based)

Cloud-based Email Services

  1. Microsoft 365 (formerly Office 365)
  2. Google Workspace (formerly G Suite)
  3. Zoho Workplace
  4. Amazon WorkMail
  5. IBM Verse
  6. Oracle Cloud Mail
  7. Salesforce Essentials
  8. HubSpot Email
  9. Freshdesk Email
  10. Zendesk Email

Enterprise Email Services

  1. Microsoft Exchange (on-premises or cloud-based)
  2. IBM Domino (on-premises or cloud-based)
  3. Novell GroupWise (on-premises or cloud-based)
  4. OpenText (formerly Symantec Enterprise Vault)
  5. Mimecast (cloud-based)
  6. Proofpoint (cloud-based)
  7. Barracuda Email Security (cloud-based)
  8. SpamAssassin (open-source, on-premises or cloud-based)
  9. Postfix (open-source, on-premises)
  10. Sendmail (open-source, on-premises)

Specialized Email Services

  1. ProtonMail Bridge (end-to-end encrypted, for businesses)
  2. Tutanota Business (end-to-end encrypted, for businesses)
  3. Mailfence (end-to-end encrypted, for businesses)
  4. StartMail (end-to-end encrypted, for individuals and businesses)
  5. Countermail (end-to-end encrypted, for individuals and businesses)
  6. Mailbox.org (end-to-end encrypted, for individuals and businesses)
  7. Riseup (end-to-end encrypted, for activists and organizations)
  8. Riseup Labs (end-to-end encrypted, for researchers and developers)

Other Email Services

  1. Discord (messaging platform with email-like features)
  2. Slack (messaging platform with email-like features)
  3. WhatsApp (messaging app with email-like features)
  4. Telegram (messaging app with email-like features)
  5. Signal (end-to-end encrypted messaging app with email-like features)

Please note that this is not an exhaustive list, and there may be other email services not included here. Additionally, some services may offer both free and paid plans, while others may be exclusively free or paid.