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