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
Windows eml and mbox viewer.
Sync Outlook with Google, SOGo or any other CalDAV / CardDAV server
Protects you from spam mails and virus mails effectively with milter
The classic email sending library for PHP
SMTP email proxy and relay server
Sync Outlook contacts and calendars with Google
E-mails, subdomains and names
Web and API based SMTP testing
Unified Communications Server
Powerful Open Source Email Marketing app with analytics & segmentation
A full-featured email creation and transfer class for PHP
An automated e-mail OSINT tool
A faster, leaner email client and fork of Nylas Mail
A program to send mail via SMTP from command line