Browse free open source Email software and projects below. Use the toggles on the left to filter open source Email software by OS, license, language, programming language, and project status.
An easy-to-use anti-spam email gateway
Anti-Spam SMTP Proxy Server implements multiple spam filters
The classic email sending library for PHP
Windows eml and mbox viewer.
Robust open source POP3 client and MIME parser written in C#
A faster, leaner email client and fork of Nylas Mail
An automated e-mail OSINT tool
Web and API based SMTP testing
E-mails, subdomains and names
Unified Communications Server
Protects you from spam mails and virus mails effectively with milter
Phishing Campaign Toolkit
A program to send mail via SMTP from command line
Sync Outlook with Google, SOGo or any other CalDAV / CardDAV server
Open source email service with a strong focus on security and privacy
Sync Outlook contacts and calendars with Google
SMTP email proxy and relay server
Take back control of your email with this mail server in a box