Mail server software privacy ratings
Software for running a mail server on your own hardware.
13 mail server software are rated against 4 public criteria, and 13 have enough evidence for a letter grade. Of the 4 with a known jurisdiction, 3 are based in a Five Eyes country, and 3 in the wider Fourteen Eyes.
Open-source mail server software only · Criteria for this category · Suggest an addition · Markdown
| Name | Grade | Score | Data | Jurisdiction | Open source | No trackers or telemetry | No ads or data sales | Independent audit |
|---|---|---|---|---|---|---|---|---|
Self-hosted mail and collaboration server written in Rust, with JMAP, IMAP, POP3, SMTP, CalDAV, CardDAV and WebDAV support, built-in spam filtering and a web admin interface. |
Grade A | 100 | 100% | United Kingdom Five Eyes | Yes | Yes | Yes | Yes |
IMAP and POP3 server for Linux and Unix that stores and serves mailboxes, with support for Sieve filtering through Pigeonhole. The Community Edition is open source. |
Grade A | 90 | 100% | Finland Outside Eyes | Yes | Yes | Yes | Partial |
Self-hosted version of the Forward Email service, installed with a script that deploys Docker containers. It includes MX, SMTP, IMAP, POP3, CalDAV and CardDAV servers, encrypted SQLite mailboxes, a web interface and optional backups to S3-compatible storage. |
Grade B | 85 | 100% | United States Five Eyes | Yes | Partial | Yes | Yes |
Self-hosted mail server in a single Docker container, with SMTP, IMAP, POP3, spam and virus filtering, configured through files and environment variables. |
Grade B | 80 | 100% | – | Yes | Yes | Yes | No |
Installer script that sets up a complete mail server on Linux or BSD from open-source components such as Postfix, Dovecot, Roundcube and SpamAssassin. |
Grade B | 80 | 100% | – | Yes | Yes | Yes | No |
All-in-one mail server written in Go that replaces Postfix, Dovecot and OpenDKIM with a single daemon, handling SMTP, IMAP, DKIM, SPF, DMARC, DANE and MTA-STS. |
Grade B | 80 | 100% | – | Yes | Yes | Yes | No |
Self-hosted mail server setup for a single Ubuntu machine, with SMTP, IMAP, webmail, contacts, calendar, spam filtering and backups preconfigured. |
Grade B | 80 | 100% | – | Yes | Yes | Yes | No |
Self-hosted mail server suite based on Docker, with SMTP, IMAP, the SOGo webmail and groupware, spam filtering and a web admin interface. |
Grade B | 80 | 100% | – | Yes | Yes | Yes | No |
Self-hosted mail server built from Docker containers, with SMTP, IMAP, webmail, spam and virus filtering and a web admin interface. |
Grade B | 80 | 100% | – | Yes | Yes | Yes | No |
Mail server written in Go for low-maintenance self-hosting, combining SMTP, IMAP, webmail, SPF, DKIM, DMARC, MTA-STS, automatic TLS and spam filtering in one program. |
Grade B | 80 | 100% | – | Yes | Yes | Yes | No |
Mail transfer agent that routes and delivers email over SMTP, used on many Linux and Unix servers as the default mail server. |
Grade B | 80 | 100% | – | Yes | Yes | Yes | No |
Self-hosted mail hosting and management platform built on Postfix and Dovecot, with a web admin interface, webmail, calendars, contacts and spam filtering. |
Grade C | 65 | 100% | – | Yes | Partial | Yes | No |
Microsoft's on-premises mail, calendar and contacts server for Windows Server, used by organizations with Outlook clients. Sold as a subscription edition. |
Grade F | 20 | 100% | United States Five Eyes | No | No | Yes | No |
Questions
What is the most private option among mail server software?
No pick has been made yet. The table above is sorted by score, based on public evidence.
How are mail server software rated?
Each entry answers 4 questions: open source, no trackers or telemetry, no ads or data sales and independent audit. Answers need links to evidence. See the full criteria.
Does jurisdiction matter?
Jurisdiction decides which laws can compel a provider to hand over data. Each entry shows its country and whether it is in the Five, Nine or Fourteen Eyes. The data a provider can hand over depends mostly on what it stores and who holds the keys. Read about jurisdictions and the CLOUD Act.