mailcow

Email Servers

A Docker-based mail server suite that bundles Postfix, Dovecot, Rspamd, SOGo webmail and a web admin interface.

Open-source alternative to:

Visit mailcow GitHub Docs

GPL-3.0Self-hostedCloudNot yet assessed

Screenshot of the mailcow website — Homepage of mailcow.email

What the free edition leaves out

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We have not been able to confirm enough from official sources to give a verdict. “Not confirmed” means the official pages we read did not say, so we do not guess.

Open-core feature checklist for mailcow
Feature	Free edition	Details	Source
SSO / SAML	Not confirmed	The docs have guides for generic OIDC and Keycloak login in the mailcow UI. SAML is not mentioned.	Source ↗
Role-based access control	Not confirmed	The ACL docs describe restrictions for domain administrators and mailbox users, but do not say whether anything is limited by edition.	Source ↗
Audit logs	Not confirmed	Not mentioned on the pages read.	Source ↗
Multi-user / teams	Not confirmed	The docs describe Administrator, Domain-Administrator and Normal User logins, but do not state any edition limits.	Source ↗
Backups and restore	Free	The docs describe a provided script, helper-scripts/backup_and_restore.sh, that backs up vmail, crypt, redis, rspamd, postfix and mysql.	Source ↗
API access	Not confirmed	No API page was found among the pages read.	Source ↗
Support SLA	Paid	The docs list community support as best-effort with no guarantees, and commercial support subscriptions and managed hosting through Servercow. No SLA terms are described.	Source ↗

Best for

Admins who want a complete self-hosted mail server for their own domains, with webmail and spam filtering, and can dedicate a server with several GiB of RAM.

Why choose it over Google Workspace

The whole stack is GPL-3.0 and installs as one Docker Compose project with a web UI, domain administrators, mailbox users, OIDC login, and a provided backup script. You keep mail data on your own server and in your own domains.

Where it falls short

The default configuration needs at least 6 GiB of RAM and 20 GiB of disk, and the docs recommend 8 GiB for about 5 to 10 users. OpenVZ, LXC and NAS devices are not supported. You handle DNS, deliverability, updates and backups yourself. Community help is best-effort; commercial support and managed hosting are sold separately by Servercow.

Open-source alternative to

Google Workspace — mailcow can replace hosted business email by running your own mail domains, mailboxes and webmail on a server you control.
Microsoft 365 — It can replace Exchange Online style mailbox hosting for your own domains with a self-run mail server.

Topics

Tech stack

Languages as reported by GitHub for the repository.