Best Open Source Mac Mail Transfer Agents 2026

Mail Transfer Agents for Mac

Mail Transfer Agents Mac Apache License V2.0 Post-Office Clear Filters

Browse free open source Mail Transfer Agents and projects for Mac below. Use the toggles on the left to filter open source Mail Transfer Agents by OS, license, language, programming language, and project status.

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1

Hedwig Mail server

Hedwig is an open source IMAP, SMTP, POP3 server written in Java, designed with ease of installation and configuration in mind. Hedwig enables storage of mail message headers in a relational database(MySQL or Oracle) and mail messages in a file system. Visit http://hwmail.sourceforge.net/ for more information.

1 Review

Downloads: 7 This Week

Last Update: 2019-01-05
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2

GreenMail

GreenMail is an intuitive and easy-to-use test suite of email servers for testing purposes. Supports SMTP, POP3, IMAP with SSL socket support, and configurable user accounts and credentials. All in 100% Java. WE'VE MOVED TO GIT HUB: https://github.com/greenmail-mail-test/greenmail

1 Review

Downloads: 0 This Week

Last Update: 2014-10-08
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3

NMail

NMail provides an SMTP client & server along with an IMAP4 server; all are written in C#.

Downloads: 0 This Week

Last Update: 2013-04-17
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4

SIMON - Java Mail Server

SIMON is a very simple MTA and POP3 implementation. It is completely designed from the ground up and is useful for departmental or small to medium sized companies.

Downloads: 0 This Week

Last Update: 2013-04-09
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