Best Open-Source Gmail / Google Workspace Alternatives (2026)
4 self-hostable, open-source projects that replace Gmail / Google Workspace — without per-mailbox fees and data privacy. Each is scored for how hard it is to self-host, with one-click deploy options where they exist.
Google Workspace charges a recurring per-mailbox fee that scales linearly with headcount, and your mail, contacts, and calendar live on Google's infrastructure subject to scanning and policy changes. Teams that want to own their data, escape per-seat billing, or keep mail on their own domain and hardware are the ones who leave.
Our picks at a glance
At difficulty 3/5 it ties Mailu for the lowest self-host difficulty here and ships a full stack (webmail, antispam, admin UI) via Docker Compose out of the box.
The most feature-complete dockerized full stack, bundling SOGo webmail, Rspamd, ClamAV, and a polished admin UI as a self-hosted Gmail replacement.
Highest momentum in this category at 18,400 stars, well ahead of mailcow's 12,900.
The only option here offering official managed hosting (managed:yes), aimed at users who want a privacy-focused service without running the server themselves.
Compare all 4 alternatives
Tap a column header to sort| Project | Deploy | Managed | License | ||||
|---|---|---|---|---|---|---|---|
 docker-mailserver Shell | 18k ★ | 4/5 Involved | Docker Docker Compose +1 | MIT | 9 days ago | Repo | |
| 13k ★ | 3/5 Moderate | Docker Compose Manual | GPL-3.0 | 11 days ago | Repo | ||
 Mailu Python | 7.3k ★ | 3/5 Moderate | Docker Compose Kubernetes +1 | MIT | 16 days ago | Repo | |
 Forward Email JavaScript | 1.3k ★ | 5/5 Advanced | Manual | BUSL-1.1 | 7 days ago | Repo |
What to look for: Running mail yourself means reliable deliverability (SPF, DKIM, DMARC, and a clean sending IP with proper reverse DNS) and ongoing spam/antivirus maintenance, so favor a stack that bundles these rather than leaving you to wire up Postfix and Dovecot by hand. Decide up front whether you want a single all-in-one container or a modular set of images, and confirm the project supports the IMAP/SMTP clients and webmail you actually need.
The alternatives, reviewed
- #1
docker-mailserverSelf-host: InvolvedProduction-ready, config-driven mail server in a single container
18k Shell MIT 9 days agoHow it compares to Gmail / Google Workspace
- No admin web UI — all config is via files and the CLI
- No bundled webmail or groupware (calendar/contacts)
- Deliverability, DNS, and TLS setup are entirely your responsibility
- Not a newsletter/marketing tool — mailboxes only
- #2
mailcow: dockerizedSelf-host: ModerateDockerized full-stack mail server, a self-hosted Gmail alternative
13k PHP GPL-3.0 11 days agoHow it compares to Gmail / Google Workspace
- Requires a dedicated server with proper DNS/PTR and good IP reputation
- Not a bulk-newsletter tool — focused on mailboxes, not campaigns
- Ongoing maintenance, updates, and spam tuning are on you
- Resource-hungry; needs a few GB of RAM minimum
- #3
MailuSelf-host: ModerateSimple yet full-featured mail server as a set of Docker images
7.3k Python MIT 16 days agoHow it compares to Gmail / Google Workspace
- No calendar/contacts groupware bundled by default
- Requires correct DNS, PTR, and IP reputation to deliver reliably
- Focused on mailboxes, not newsletters or marketing campaigns
- Upgrades occasionally require manual migration steps
- #4
Forward EmailSelf-host: AdvancedPrivacy-focused email service, an all-in-one Gmail and SaaS alternative
1.3k JavaScript BUSL-1.1 7 days agoHow it compares to Gmail / Google Workspace
- Self-hosting is complex and far less documented than the hosted service
- Newsletter/campaign tooling is thin compared to Mailchimp
- BUSL-1.1 license is source-available, not fully OSI-open
- Running production email requires significant infra and DNS expertise
The verdict
For most teams self-hosting business email, mailcow is the best balance of completeness and approachability; pick docker-mailserver if you prefer a leaner single-container, config-driven setup, or Forward Email if you'd rather not operate the server at all.
Gmail / Google Workspace alternatives — frequently asked questions
Is there a free open-source Gmail alternative I can self-host?
Yes. docker-mailserver (MIT) and Mailu (MIT) are both free and permissively licensed, and mailcow (GPL-3.0) is free and open source as well. All three run on your own hardware via Docker.
Which self-hosted mail server is easiest to set up?
mailcow and Mailu are the most approachable at difficulty 3/5, both deploying via Docker Compose with batteries included. docker-mailserver is slightly harder at 4/5, and Forward Email is the most involved at 5/5.
Do any of these offer managed hosting instead of self-hosting?
Only Forward Email offers an official managed service. mailcow, Mailu, and docker-mailserver are self-host only, so you provide the server and handle operations yourself.
Which has the most community momentum?
docker-mailserver leads with 18,400 stars, followed by mailcow at 12,900 and Mailu at 7,300.
Will my email actually be delivered if I run my own server?
It can, but deliverability is the hard part of self-hosting mail. All of these expect you to configure SPF, DKIM, and DMARC and use an IP with good reputation; mailcow and Mailu bundle Rspamd-based spam filtering to help on the inbound side.
Can I use a normal email client with these?
Yes. docker-mailserver, mailcow, and Mailu are standard IMAP/SMTP servers, so Thunderbird, Apple Mail, and mobile clients work; mailcow and Mailu also include webmail.