Posteo

Posteo is an independent, advertising-free email service. A paid account starts at €1 per month and includes email, calendar, address book and notes, reachable through their webmail and web app or through any client that speaks IMAP or POP3. Accounts are opened without personal details, there is no tracking or user profiling, and payment data is never linked to a mailbox, so no name, address or IP records are held for its customers.

Mailboxes start at 4 GB with three alias addresses, both upgradeable, and the security model is broad rather than bolted on: two-factor login with TOTP, mandatory TLS transport with DANE, PGP or S/MIME encryption on inbound mail, PGP inside the webmail interface with a key directory, encrypted hard drives, and one-click encryption for the mailbox, calendars, address book and notes. Calendars sync over CalDAV and are shared by ICS link, the address book uses CardDAV with VCF import and export, and a self-developed migration service moves in existing mail, appointments and contacts over an encrypted connection without third parties; three migrations are included per account. Servers sit in German data centres, with daily backups of stored data.

The service is run by Posteo e.K. of Berlin, which was founded in 2009 and now employs more than 40 people. It is financed entirely by its users — more than half a million accounts — with no advertising partners and no investors, and runs on 100% green electricity from Green Planet Energy, having taken no business flights since it was founded. In May 2014 it became the first German telecommunications provider to publish a transparency report on requests for user data, and has kept publishing one since; it has twice been a Stiftung Warentest test winner and received the German Fairness Award in 2024.