Self-host Mailu

updated Jul 2026deployed by usprices checked · Jul 2026Install verified on Ubuntu 26.04 · Jul 2026 · how we test

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A simple, full-stack mail server as a set of Docker images — SMTP/IMAP, webmail, antispam, and an admin panel generated by a setup wizard. A lighter, MIT-licensed self-hosted alternative to Google Workspace for personal and small-team email. As with any self-hosted mail, expect to manage deliverability (SPF, DKIM, DMARC, and reverse DNS) so your mail reaches inboxes.

Key facts

CategoryMail Server

LicenseMIT

StackPython, Shell

Min RAM1024 MB

Official imageyes

Difficulty

Sourcegithub.com/Mailu/Mailu

Websitemailu.io

Our recommendation

Pick Mailu when you want a full mail stack with a web admin and optional webmail (Roundcube or SnappyMail) on far less hardware than Mailcow: the compose requirements are 1 GB of RAM plus 1 GB of swap without antivirus, 3 GB with ClamAV enabled. It is MIT-licensed and assembled by a web wizard at setup.mailu.io that writes your `docker-compose.yml` and `mailu.env` — which is also its quirk: the documented install path is the wizard, and every upgrade goes back through it.

Follow the Mailu deploy guide →

What you need

Any VPS with at least 1024 MB of RAM
A domain you control — most self-hosted setups need HTTPS in front of them
About the better part of a day

Where to host itaffiliate disclosure

Hetzner Cloudrun it on

From $23.59/mo · 2 vCPU / 4 GB / 80 GB · EU + US

Get Hetzner Cloud

Kamaterafree trial

From $4/mo · 1 vCPU / 1 GB / 20 GB · US + EU + Asia

Start free on Kamatera →

DigitalOceanalso works on

From $6/mo · 1 vCPU / 1 GB / 25 GB · US + EU + Asia

Deploy on DigitalOcean →

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Install

Run these commands on your server:

# Mailu has no one-line install. First complete the wizard at
#   https://setup.mailu.io
# and copy the docker-compose.yml + mailu.env it generates into this
# directory — the commands below fail without them.
docker compose up -d
docker compose exec admin flask mailu admin me example.net 'CHANGE_ME'

deploy guideHow to Deploy Mailu on a VPS vps picksBest VPS for self-hostingbenchmarked quarterly · re-priced monthly

What you take on

Mailu's requirements page is short and strict; the things that break installs are all on it:

non-negotiableThe host must not listen on ports 25, 80, 110, 143, 443, 465, 587, 993, 995 or 4190, and should have a public IP configured; upstream highly recommends a dedicated IP and hostname with matching forward and reverse DNS. The docs also say that if you switched the host to nftables you will have to roll back until Docker supports it.

non-negotiableRAM is 1 GB + 1 GB swap without antivirus, 3 GB + 1 GB swap with it; the wizard itself says ClamAV needs at least 1 GB just to load its signature database. Our 1 GB floor is the no-antivirus figure.

non-negotiableVersions are named Year.Month.Minor (the wizard currently offers 2024.06) and the release notes say you can only go forward — downgrades work only between minors of the same release. Upgrading means regenerating both files through setup.mailu.io and reading the Upgrading section first; master is the development branch.

non-negotiableBehind a reverse proxy the FAQ calls REAL_IP_HEADER and REAL_IP_FROM vital, and before enabling IPv6 you must disable Docker's userland-proxy or, in the docs' words, create an open relay.

non-negotiableAfter docker compose up -d there are no accounts: create the first admin with docker compose exec admin flask mailu admin me example.net 'password', then generate SPF, DKIM and DMARC from the domain's admin page and add them at your registrar.