iRedMail is #4 in Top 10 Email Servers
Open Source Mail Server Solution. The right way to build your mail server with open source softwares. Works on Red Hat, CentOS, Debian, Ubuntu, FreeBSD, OpenBSD.
Positions in ratings
#4 in Top 10 Email Servers
Alternatives
The best alternatives to iRedMail are: Zimbra, Postfix, Microsoft Exchange, mailcow, hMailServer, Roundcube