A mail server you own: your domain, your storage, no scanning of correspondence. Mailcow and Mail-in-a-Box bundle everything (SMTP, IMAP, antispam, webmail) in one deployment; stalwart-mail-server and mox are lean modern single-binary options for smaller setups.
Open source alternatives to Gmail
A mail server you own: your domain, your storage, no scanning of correspondence. Mailcow and Mail-in-a-Box bundle everything (SMTP, IMAP, an…
Compare
| Program | License | Self-hosted | Last release | Activity |
|---|---|---|---|---|
| Mailcow | GPL-3.0 | Yes | Oct 21, 2026 | Nov 2026 |
| Mail-in-a-Box | CC0-1.0 | Yes | Sep 26, 2026 | Oct 2026 |
| Stalwart Mail Server | — | Yes | Nov 4, 2026 | Nov 2026 |
| Mox | MIT | Yes | Aug 19, 2026 | Oct 2026 |
| docker-mailserver | — | Yes | — | — |
| Modoboa | — | Yes | — | — |
| Mailu | — | Yes | Oct 23, 2026 | Nov 2026 |
| iRedMail | GPL-3.0 | Yes | Oct 28, 2026 | Oct 2026 |
| Maddy Mail Server | GPL-3.0 | Yes | Oct 3, 2026 | Nov 2026 |
| Simple NixOS Mailserver | — | Yes | Dec 16, 2019 | Nov 2026 |
| Inboxen | — | Yes | — | — |
| DebOps | — | Yes | — | — |
| AnonAddy | — | Yes | — | — |
| b1gMail | GPL-2.0 | Yes | Feb 23, 2025 | Nov 2026 |
| SimpleLogin | AGPL-3.0 | Yes | Nov 4, 2026 | Nov 2026 |
Mailcow
v2026-10
★ 13,743
Mail-in-a-Box
Turns fresh Ubuntu into a mail server for individuals managing their own email
v77
★ 15,456
Stalwart Mail Server
v1.0.3
★ 15,733
Mox
v0.0.17
★ 5,931
docker-mailserver
Modoboa
Mailu
v2024.06.67
★ 7,602
iRedMail
★ 1,850
Maddy Mail Server
v0.9.6
★ 6,120
Simple NixOS Mailserver
v2.3.0
★ 321
Inboxen
DebOps
AnonAddy
b1gMail
v7.4.1-pl2
★ 30
SimpleLogin
v4.83.4
★ 7,115
How to choose
Compare the options on what matters for your case: the license (if you run a business, check commercial use), the platforms you already operate, and how actively each project releases. Every program above links to its official project page, release notes and source code.
Questions
Is running my own mail server hard?
The all-in-one bundles make it manageable: one VPS, correct DNS records, and you are done. Deliverability is the part to watch.