head to head · open source
Billion Mail vs Mautic
Billion Mail has 15,611 GitHub stars, 1,702 forks, 236 open issues and last shipped 3 months ago. Mautic has 10,525 stars, 3,448 forks, 193 open issues and last shipped yesterday. Billion Mail leads on adoption by 48% (15,611 vs 10,525 stars). Billion Mail is written in Go under AGPL-3.0; Mautic is written in PHP under a custom or non-standard licence. Billion Mail has attracted 11% as many forks as stars, Mautic 33%. Mautic was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 1 topic tag (email-marketing), so they are genuine substitutes rather than adjacent tools.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| Billion Mail | Mautic | |
|---|---|---|
| GitHub stars | ★ 16K | ★ 11K |
| License | AGPL-3.0 | Custom / other |
| Written in | Go | PHP |
| Last push | 2026-06-11 | 2026-09-17 |
| Forks | ⑂ 1.7K | ⑂ 3.4K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Billion Mail if
- You weight community size — 16K stars and counting
- You want the AGPL-3.0 license terms
- Your stack matches Go
- You value the larger contributor base for long-term maintenance
pick Mautic if
- You want the Mautic feature set and don't need the biggest community
- You prefer the Custom / other license terms
- Your stack matches PHP
- You evaluated both and Mautic fits your workflow better
About Billion Mail
BillionMail is an open source mail server and email marketing platform written in Go and released under the AGPL 3.0 license. It lives in the self hosted email ecosystem and is described as a solution for newsletters, promotional emails, and transactional messages. The project combines mail server topics such as Postfix, Dovecot, Rspamd, and SMTP with campaign features such as customer management, analytics, templates, and sending control.
read the full Billion Mail overview →
About Mautic
Mautic is open source marketing automation software written in PHP. It lives in the PHP open source marketing automation ecosystem and positions itself as an alternative to Mailchimp and SendGrid. It targets businesses and organizations that need campaign delivery, audience segmentation, email marketing, multi channel messaging, and direct control over marketing data.
read the full Mautic overview →
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Frequently asked questions
Is Billion Mail or Mautic more popular?
Billion Mail has 15,611 GitHub stars and Mautic has 10,525. Billion Mail has the larger community by that measure.
Are Billion Mail and Mautic free?
Both are open source. Billion Mail is licensed under AGPL-3.0, and Mautic has no licence declared in this registry. Both are free to self-host.
What is the difference between Billion Mail and Mautic?
Billion Mail is written in Go and Mautic in PHP. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Billion Mail or Mautic?
Choose Billion Mail if you want the larger community (15,611 stars) or its AGPL-3.0 licence terms. Choose Mautic if its feature set, stack or Custom / other licence fits better. Both are self-hostable.