Alternatives to Postfix for all platforms with any license

Exim

Exim is a message transfer agent (MTA) developed at the University of Cambridge for use on Unix systems connected to the Internet.

Free Open Source Mac Windows Linux
No features added Add a feature

12 Like
MailHog

MailHog is an email testing tool inspired by MailCatcher, but easier to install. - Configure your application to use MailHog for SMTP delivery - View emails in the web...

Free Open Source Mac Windows Linux
Portable Add a feature

5 Like
sSMTP

sSMTP is a simple MTA to deliver mail from a computer to a mail server. sSMTP is simple and lightweight, there are no daemons or anything hogging up CPU; Just sSMTP....

Free Open Source Linux
No features added Add a feature

3 Like
OpenSMTPD

OpenSMTPD is a FREE implementation of the server-side SMTP protocol as defined by RFC 5321, with some additional standard extensions. It allows ordinary machines to...

Free Open Source Linux BSD Self-Hosted
No features added Add a feature

3 Like
Haraka

Haraka is an open source SMTP server written in Node.js which provides extremely high performance coupled with a flexible plugin system allowing Javascript programmers...

Free Open Source Self-Hosted Node.JS
Support for Javascript Add a feature

3 Like
msmtp

In the default mode, it transmits a mail to an SMTP server (for example at a free mail provider) which takes care of further delivery. To use this program with your...

Free Open Source Linux Xfce
No features added Add a feature

3 Like
Sendmail

Sendmail is a general purpose internetwork email routing facility that supports many kinds of transfer and delivery methods, including the Simple Mail Transfer Protocol...

Free Open Source Mac Linux
No features added Add a feature

3 Like
MailerQ

MailerQ is a high performance Mail Transfer Agent (MTA) and a very fast SMTP server, designed to deliver large volumes of email messages at very high speeds. MailerQ is...

Commercial Linux
Management Console Add a feature

3 Like
Microsoft SMTP Server

Configure SMTP e-mail in IIS when you want to deliver e-mail messages from your site. Mail can be delivered immediately or it can be delivered to a file location on disk...

Commercial Windows
Email Forwarding Add a feature

1 Like
NikaMail

NikaMail is a portable, extendable, zero-config email server. It is designed to perform automation tasks, provide access to mailboxes (port 110), serve as a mail...

Free Open Source Mac Linux
Exchange email POP3 Support Add a feature

1 Like
Courier-MTA

The Courier mail transfer agent (MTA) is an integrated mail/groupware server based on open commodity protocols, such as ESMTP, IMAP, POP3, LDAP, SSL, and HTTP. Courier...

Free Open Source Mac Linux BSD Self-Hosted
No features added Add a feature

7 Like
PowerMTA

Email gateway application (SMTP server) that makes it easy for senders to adopt the latest authentication specifications ( SPF and DKIM) to comply with changing ISP...

Commercial Windows Linux Self-Hosted
No features added Add a feature

1 Like
EmailSuccess

EmailSuccess, an advanced SMTP Server (MTA) built from the ground up to handle the most critical reliability, performance, security, and deliverability requirements.

Commercial Linux Java
Email deliverability Management Console On-premises software Encrypted email Add a feature

1 Like
esmtp

esmtp is a user configurable relay-only Mail Transfer Agent (MTA) with a sendmail compatible syntax. It's based on libESMTP supporting the AUTH (including the...

Free Open Source Linux BSD
No features added Add a feature

0 Like
Go-Guerrilla

A lightweight SMTP server written in Go, made for receiving large volumes of mail. To be used as a package in your Go project, or as a stand-alone daemon by running the...

Free Open Source Web
No features added Add a feature

0 Like