Postfix is described as 'Mail transfer agent (MTA) that routes and delivers electronic mail. It attempts to be fast, easy to administer, and secure. The software is also known by its former names VMailer and IBM Secure Mailer' and is a Mail Server in the online services category. There are more than 25 alternatives to Postfix for a variety of platforms, including Linux, Mac, Windows, Self-Hosted and BSD apps. The best Postfix alternative is Mail-in-a-box, which is both free and Open Source. Other great apps like Postfix are Mailpit, Stalwart, MailHog and KumoMTA.
A small Mail Transport Agent (MTA), designed for home and office use. Part of DragonFly BSD , it accepts mails from locally installed Mail User Agents (MUA) and delivers the mails either locally or to a remote destination.
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 where it can be retrieved for delivery later.
United States
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 based on RabbitMQ AMQP.
Netherlands
EU
Halon is a global leader in email infrastructure, empowering large senders and mailbox providers to maximize email. Founded in 2010, Halon's solutions process billions of emails daily worldwide.
SwedenEU
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 transfer agent (port 587) and mail exchange service (port 25). NikaMail supports TLS.
An SMTP client that is extremely easy to configure and use, providing a simple HTTP API that is used for sending emails.
Mailsnag lets you build resilient SMTP integrations while protecting you from spamming customers during testing on QA and Staging environments. It is like Chaos Monkey for SMTP integrations.
United States
A lightweight mail server with SMTP and POP3 support. It mainly used as store-and-forward mail server with POP access to spooled messages or it can be used as a personal internet mail server.
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 "guerrillad" binary.
Germany
