Traditional email platforms come with a long list of limitations —
Restricted features, sending limits, and data privacy concerns.
With closed-source solutions, it’s a black box: when something goes wrong, you have no idea why or where.
BillionMail completely changes the game.
It’s an open-source email server developed by the aaPanel team, offering a complete self-hosted email marketing solution.
From zero to sending — you can build your own email marketing system in just 8 minutes.
BillionMail integrates multiple key features —
From the email server to marketing management and contact lists, everything is handled in one place.
Its fully open-source architecture frees you from vendor lock-in.
The code is transparent and fully customizable.
It comes with Postfix, Dovecot, and Rspamd built-in — proven components that ensure stability and reliability.
You get unlimited email sending — no more worrying about hitting your quota.
With advanced analytics, you can track delivery rates, open rates, and click-through rates in real time.
It also includes RoundCube webmail integration, accessible directly via the /roundcube/ path, making daily email sending and receiving extremely convenient.
And best of all, deployment is incredibly simple.
Deployment can be completed with just three commands:
For Docker users, there’s a dedicated setup available.
Simply copy the environment configuration file and start the service directly using Docker Compose.
Domain setup is incredibly beginner-friendly.
Simply add your sending domain, verify the DNS records, and the system will automatically enable free SSL certificates.
There’s almost no manual configuration required, making management and maintenance both easy and efficient.
BillionMail also provides a full-featured command-line tool:
-
bm help– View command help -
bm default– Show default login credentials -
bm show-record– Display DNS records for domain setup -
bm update– One-click upgrade to the latest version
A live demo environment is also available at:
👉 demo.billionmail.com/billionmail
Both the username and password are: billionmail
The technical architecture is professional and reliable.
Built on the Go programming language, it delivers excellent performance.
About 6.2% of the codebase is Shell scripts, mainly used for deployment and management.
The project is licensed under the AGPLv3 license, ensuring it remains fully open-source and protected from being closed-source for commercial use.
The Docker image includes four core components:
-
postfix -
dovecot -
core -
rspamd
The architecture is clear and modular.
So far, 8 versions have been released, with the latest being v2.2.
There are 5 core contributors, and the community remains active and supportive.
Compared to commercial SaaS email services that can cost thousands per month,
BillionMail offers a significant cost advantage.
When self-hosted, the server costs are minimal and can be spread out over time — almost negligible.
You own your data completely, with no dependence on third-party platforms or policy changes.
Even if external services go offline, your system stays running.
Need new features? Just edit the code yourself — the flexibility is unmatched.
👉 Project repository: https://github.com/aaPanel/BillionMail
