Mail-in-a-Box

Self-Hosted

Self-hosted email server in a box

Overview

Mail-in-a-Box is a self-hosted, all-in-one email solution that simplifies setting up a full-featured mail system. It includes IMAP/SMTP, webmail, CalDAV/CardDAV (calendar/contacts), spam filtering, and automated DNS config (DKIM, SPF, DMARC) for deliverability. Deployment uses a single shell script on Ubuntu (20.04/22.04) with a domain. It offers backup tools and an admin interface to manage accounts and server settings, putting you in control of your email data.

Self-Hosting Resources

Find Official Image on Docker Hub View Source & Docs

Below is a reference structure for docker-compose.yml. ⚠️ Do NOT run blindly. Replace placeholders with official values.

docker-compose.template.yml TEMPLATE


version: '3'
services:
  mail_in_a_box:
    image: <OFFICIAL_IMAGE_NAME>:latest
    container_name: mail-in-a-box
    ports:
      - "8080:<APP_INTERNAL_PORT>"
    volumes:
      - ./data:/app/data
    restart: unless-stopped

Key Features

All-in-one email, calendar, and contacts server
Automated DKIM, SPF, DMARC setup for email deliverability
Webmail access and CalDAV/CardDAV integration

Frequently Asked Questions

? Is Mail-in-a-Box hard to install?

No—Mail-in-a-Box uses a single shell script to automate installation on an Ubuntu server. You need a VPS with Ubuntu (20.04/22.04) and a domain name; run the setup command to get your server up quickly.

? Is it a good alternative to Gmail Workspace?

Yes, if you prioritize data privacy and control. Unlike Gmail Workspace, it’s self-hosted, but it requires more maintenance (server updates, deliverability checks) than a managed SaaS service.

? Is it completely free?

Yes—Mail-in-a-Box is open-source (MIT License) with no software fees. You only pay for the VPS and domain name to host your server.

Top Alternatives

Gmail Workspace Search Google

Microsoft Outlook 365 Search Google

Zoho Mail Search Google

Tool Info

Pricing Free/Open Source

Category Communication - Email - Complete Solutions

Platform Self-Hosted

Pros

⊕ Privacy-focused (self-hosted email data control)
⊕ No recurring subscription fees
⊕ Simplified one-command installation

Cons

⊖ Requires Ubuntu server maintenance
⊖ Technical knowledge for initial setup and troubleshooting
⊖ Email deliverability may need ongoing monitoring (e.g., IP reputation)