Mailcow

★ 10k

Dockerized full mail server suite — SMTP, IMAP, webmail, antispam, DKIM — with a slick admin UI.

Mailcow does the job of Google Workspace, self-hosted. It is GPL-3.0-licensed, a copyleft licence, and setting it up is an afternoon, not a weekend. Google Workspace bills $7/user for it. 10k stars on GitHub.

Open-source replacement for Google Workspace.

Licence: GPL-3.0
Self-hosting: Medium
The paid one costs: $7/user
GitHub stars: 10k

view the code →official site →

Is it actually a replacement?

We have written a verdict on what it replaces — what you lose, and why people still pay:

Can I open-source Google Workspace Business Starter? →

How Mailcow runs

Where it runs

Mailcow runs on your server.

What setup takes

not verified by us yet — check the repo README.

Mailcow questions

Is Mailcow open source?

Yes — it is released under GPL-3.0.

Can Mailcow replace Google Workspace?

Our verdict on Google Workspace Business Starter is YES. Nextcloud Hub (36k stars), Jitsi Meet (25k stars), LiveKit (13k stars) are mature open-source replacements for Google Workspace Business Starter — self-host with real ops work and stop paying $7/mo.

Can I self-host Mailcow?

Yes — we rate it medium to self-host, and it runs on your server.

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