Open source email projects
Every project in the registry tagged email, ranked by real GitHub adoption.
Open-source mail server with unlimited sending & AI tools
BillionMail gives you open-source MailServer, NewsLetter, Email Marketing — fully self-hosted, dev-friendly, and free from monthly fees. Join the discord: http
Secure, seamless authentication for modern applications
AI email assistant that automates, organizes, and declutters
Low code web framework for real world applications, in Python and Javascript
Prometheus Alertmanager
Secure email, calendar and contacts with end-to-end encryption
Drag-n-Drop Email Editor Component for React.js
Pay per email sent, not for contact storage
Open-source customer engagement platform for automation
Bichon – A lightweight, high-performance Rust email archiver with WebUI
Transform team email into efficient collaborative workflows
Free email OSINT tool, 5000+ platforms, identity clustering, breach detection. No API keys required. pip install mailaccess
Decentralized private messenger with chat-shared tools and games for Desktop
The affordable newsletter for the agentic era. Open source: self-host it, or use mailcheap.ai.
Free HTML email templates for Mailchimp and other emails services
Own your SES email analytics, from send to inbox
Open-source email API with enterprise deliverability
The largest open-source B2B cold outreach and email warmup service.
Secure open source email with advanced encryption & AI
Code-first email platform that deploys to your AWS
Related tags
Frequently asked questions
How many open source email projects are there?
This registry tracks 27 projects tagged email, with 184,812 GitHub stars between them. The most-adopted is novu at 40,247 stars.
Are these email projects free to use?
Yes — 22 of the 27 carry an explicit open-source licence across 5 distinct licences, so there is no licence fee. Where a project also sells a hosted or enterprise version, the self-hosted path remains free.
Which email project should I choose?
The list above is ranked by GitHub stars, but stars measure attention rather than fit. Check three things on each card: the licence (permissive versus copyleft), the language it is written in, and the last-push date — a high-star project that has not been pushed in a year is a liability.
Are these email projects still maintained?
24 of the 27 were pushed in the last 90 days, and every card shows its exact last-push date so you can see the rest. Sort your shortlist by that date before committing to a migration.