Mailcow is the best choice for most self-hosters — it has the best web UI, easiest updates (Docker pull), and largest community. iRedMail offers the most flexibility with multiple distro and database support, making it ideal for integration into existing infrastructure. Modoboa is the lightest option (runs on 1GB RAM), good for small deployments on budget VPS. All three use Postfix and Dovecot under the hood — the difference is management and packaging.
Mailcow vs. iRedMail vs. Modoboa: Which Self-Hosted Email Server?
Three Platforms, One Stack, Different Philosophies
Mailcow, iRedMail, and Modoboa all install Postfix (SMTP) and Dovecot (IMAP) as their email engine. The difference is how they package, manage, and present that stack. Think of them as different cars built on the same chassis.
Feature Comparison
| Feature | Mailcow | iRedMail | Modoboa |
|---|---|---|---|
| Installation | Docker Compose | Shell script | Python installer |
| Container-based | Yes (Docker) | No (bare metal) | No (bare metal) |
| Min RAM | 2-4 GB | 2 GB | 1 GB |
| Web admin UI | Excellent | Basic (free) / Good (Pro $) | Good |
| Webmail | SOGo | Roundcube/SOGo | Roundcube |
| Anti-spam | Rspamd | SpamAssassin/Rspamd | SpamAssassin/Rspamd |
| Virus scanning | ClamAV | ClamAV | ClamAV (optional) |
| Multi-domain | Yes | Yes | Yes |
| DKIM management | UI-based | Manual/CLI | UI-based |
| API | Yes (REST) | Limited | Yes (REST) |
| Updates | docker compose pull | Package manager | pip + git pull |
| OS support | Any with Docker | Ubuntu, Debian, Rocky, OpenBSD | Ubuntu, Debian |
| Database | MySQL | MySQL, PostgreSQL, LDAP | MySQL, PostgreSQL |
| Community | Large | Large | Small |
| License | GPL | Apache/GPL | ISC |
Installation Experience
Mailcow
git clone https://github.com/mailcow/mailcow-dockerized
cd mailcow-dockerized
./generate_config.sh
docker compose pull
docker compose up -d
Five commands. 15 minutes. The web UI handles everything else. This is why Mailcow dominates — the installation experience is nearly flawless.
iRedMail
wget https://github.com/iredmail/iRedMail/archive/1.7.1.tar.gz
tar xzf 1.7.1.tar.gz && cd iRedMail-1.7.1
bash iRedMail.sh
The installer asks more questions — database backend, web server, optional components. More control, more decisions. 20-30 minutes.
Modoboa
git clone https://github.com/modoboa/modoboa-installer
cd modoboa-installer
sudo python3 run.py yourdomain.com
Generates a config file you review before final installation. 15-20 minutes. Clean process, minimal interaction.
Resource Usage in Practice
Tested on identical Hetzner CX22 instances (2 vCPU, 4GB RAM, Ubuntu 22.04):
| Metric | Mailcow | iRedMail | Modoboa |
|---|---|---|---|
| RAM (idle) | 2.1 GB | 1.4 GB | 0.7 GB |
| RAM (with ClamAV) | 2.8 GB | 2.1 GB | 1.4 GB |
| Disk (base install) | 4.2 GB | 1.8 GB | 1.2 GB |
| Docker images | 3.1 GB | N/A | N/A |
| Containers/processes | 16 | 8 | 7 |
Mailcow's Docker architecture adds overhead. If you're on a 2GB VPS, Mailcow will struggle. Modoboa runs comfortably on 1GB.
When to Choose Each
Choose Mailcow If:
- You want the best admin experience with minimal command-line work
- You're comfortable with Docker
- You have 4GB+ RAM available
- You want the largest community for troubleshooting
- You plan to use the API for automation
Choose iRedMail If:
- You need to run on a specific distro (Rocky Linux, OpenBSD)
- You want LDAP integration for existing directory services
- Docker isn't an option (policy or infrastructure constraints)
- You need PostgreSQL specifically
- You have sysadmin experience and want direct config access
Choose Modoboa If:
- You're on a budget VPS with 1-2 GB RAM
- You want a web admin without Docker overhead
- Your deployment is small (few domains, few users)
- You prefer Python/Django stack for potential customization
Practitioner note: I deploy Mailcow for 80% of my self-hosted email projects. The web UI saves my clients hours of management time, and Docker Compose updates are foolproof. The 20% that go with iRedMail are organizations with existing Linux infrastructure and sysadmins who prefer bare-metal installations they can inspect directly.
Practitioner note: Modoboa is underrated. I set it up for a freelancer who needed email for three domains on a $4/month Hetzner instance. It's been running for over a year with zero issues. Not every project needs Mailcow's full stack — sometimes the lightest tool is the right tool.
If you're stuck choosing between these platforms, schedule a consultation — I'll evaluate your specific requirements, volume, and technical team to recommend the right fit.
Sources
- Mailcow: Documentation
- iRedMail: Documentation
- Modoboa: Documentation
- Docker: System Requirements
v1.0 · April 2026
Frequently Asked Questions
Which is easiest to install?
Mailcow. Docker Compose install takes 15 minutes with minimal prompts. Modoboa's installer is second-easiest. iRedMail's installer has more choices (database backend, components) which adds complexity but also flexibility.
Which has the best web admin panel?
Mailcow, by far. Its web UI is modern, comprehensive, and covers everything — domains, mailboxes, DKIM, queue management, logs, and two-factor auth. Modoboa's UI is clean but less feature-rich. iRedMail's free panel (iRedAdmin) is basic; the Pro version is paid.
Which uses the least resources?
Modoboa runs on 1GB RAM without ClamAV. iRedMail needs 2GB minimum. Mailcow needs 2-4GB because Docker overhead and multiple containers add up. If you're on a tiny VPS, Modoboa wins.
Which is best for GoHighLevel or SMTP relay?
None of these are ideal relay platforms — they're mailbox servers. For SMTP relay to GHL, Postal or KumoMTA are better. But if you must use one, Mailcow's Postfix configuration is the easiest to modify for relay use.
Can I migrate between them?
Yes. All three use Postfix and Dovecot with Maildir storage. Migrate mailboxes with imapsync, recreate DNS records, and import user accounts. The data layer is compatible; only the management layer differs.
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