14 Best Linux Mail Servers in 2024 (Free + Open Source)

Ever had a promotion email from a company? Who hasn’t, right? Even if you have been using Gmail or another free mail service until now, you’ve had quite a few run-ins with mail servers. With the clear importance of mail servers, it is difficult to imagine launching a successful business without taking advantage of the best mail servers. To manage your daily backlog of emails, you need the best Linux email server around. This blog post will help you select the best mail servers for Linux. Let us now dive in to learn more about the top 14 of the best Linux mail servers.

What is a Mail Server?

A Linux mail server software is used for transferring emails from one point of the Internet to another. Also known as Mail Transfer Agents (MTAs), they receive incoming emails from other servers before forwarding them to the user’s client software and vice versa. Although almost all mail servers handle both incoming and outgoing emails, the two functions are separate and follow different protocols. An incoming mail server usually operates using the Post Office Protocol 3 (POP3) or the Internet Message Access Protocol (IMAP), while Simple Mail Transfer Protocol (SMTP) is used to send the emails they have previously received from the user’s client software.

What Are the Requirements for Hosting a Linux Mail Server?

The advantages of hosting your own mail server are improving the security and privacy of your emails and performing email marketing campaigns more effectively. A Linux distro is the perfect choice for hosting mail servers as Linux is lightweight, highly customizable, and doesn’t take much of your hardware resources. Even with a Linux OS, you still need a whole other computer with enough storage and memory resources to act as your mail server. Now, buying a computer with the right specs can get expensive. That’s why hosting your mail server on a VPS is a great option.

A virtual private server is a hosting service that acts like a virtual computer. You can get a VPS with a Linux distro entirely dedicated to your Linux mail server software. Cloudzy is just the right solution for hosting the best Linux mail servers. Cloudzy’s Linux VPS is available in more than 15 locations across 3 continents, allowing you to host your mail server close to your customer base or anywhere you desire. These virtual private servers are extremely powerful since Cloudzy uses the latest hardware resources for backing the servers. You can choose the resources you need to host your Linux mail server, and as your business grows, you can easily scale your plans up.

Overall, VPS is an affordable solution, but Cloudzy is known for offering the most budget-friendly prices, which is beyond remarkable considering the high-quality services. Bonus fact: If you get your VPS for mail server from Cloudzy, you’ll get your Linux OS free and pre-installed. We offer a complete selection of Linux distros.

How to Choose the Best Mail Servers for Linux?

When looking for a mail server, there are many things you need to consider.

The most important factors are the features the server offers and how well it meets your needs. Some features to look for include support for different mail clients and integration with your existing software and hardware. Make sure the mail server has the features you need to run your business efficiently.

Another critical factor is the size of your organization. If you have a small business with only a few users, then a small mail server may be all you need. However, if you have a large number of users, then you’ll need a more powerful server.

You should also consider the cost of the server and whether or not it will fit into your budget. They can range in price from several hundred dollars to thousands of dollars.

Before you make a final decision, be sure to test out several different servers to find the one that is right for you. This will help ensure that you get the best possible service and are happy with your choice.

14 Best Mail Servers for Linux

When a Sendmail server receives an e-mail, it attempts to immediately deliver that to the intended recipient. If the recipient is not present, it queues messages to deliver them later. In fact, it doesn’t provide any mailbox facility. So, other software such as Internet Message Access Protocol and POP3 are needed. Some of the best features of this Linux mail server software are:

• Reliability in message delivery
• Needs very little network bandwidth
• Customized email forwarding capabilities
• Using configuration files to control mail configuration

It is an open-source and free software that works under GNU General Public License (GPLv2 and GPLv3). This Linux mail server is mostly known for its simple control panel and efficient runtime. Moreover, it has a lot of good features, some of which are listed below:

• Shared calendar
• Instant messaging
• A convenient address book
• Scheduler
• File storage
• Jabber alongside SSL/TLS encryption
• OpenSSL encryption
• Built-in implementations of Internet Protocols such as POP3, IMAP, SMTP, and XMPP
• Web-based user interface based on Ajax-style functionality for application-like interactions
• OPeNDAP and Microsoft Active Directory support

Modoboa is widely deployed with SPF and DKIM protocols using DMARC. These protocols are free email authentication technologies for email delivery and security that, through a reporting function, help senders and receivers boost and monitor the protection of the domain against fraudulent email. The cool thing is that it lets you configure a fully functional mail server through the most important features you can benefit from, including:

• Webmail
• Calendars management
• Address books management
• Creating visualized filtering rules to organize emails
• Auto-responder
• Supporting multiple domains, mailboxes, and aliases
• Administrator tools that help you monitor the traffic

Exim is a free software that has been incorporated into most UNIX-like systems. Its fourth version is the default MTA on Debian Linux systems. Some of the best features of this mail server are:

• The external authenticator
• Pre-built support for a large number of database management systems such as MYSQL, Oracle DB, SQLite, PostgreSQL, and Redis
• Encrypted SMTP connections using SSL/TLS
• Straightforward configuration, customization, and task management
• Three log mechanisms i.e. main log, panic log, and reject log
• Local scan function
• System-wide message filtering
• Message processing
• GNU GPL license

• Junk mail control
• Database support
• Fast and secure
• Flexibility in administration
• Convenient log management
• Defense against spambots
• Pre-packed content filtering
• Virtual domain support
• Configurable status notification
• Support for many standard databases, including MYSQL, SQLite, PostgreSQL, LDAP, Memcached, CDB, and Berkeley Database

This mail server consists of many programs that run in the background and a few that interact with the user processes. You can imagine the whole system as a router because it looks at the IP packet and determines the destination and resource IP address exactly like a router. Then, it selects the right interface to route the mail toward its destination.

• Integrated mailing list server
• Fully automatic migration tool
• Antivirus and antispam integration options
• Malware and spam protection mechanism
• A convenient address book
• Unmatched manageability for administrators
• Various mobile capabilities, including mobile-friendly webmail and Exchange Active Sync support
• Can be hosted in data centers, on bare-metal, private or public cloud servers and VPS.
• Multiple, customizable advertising and branding options
• Integrated Web-Admin and Web-Mail client
• 60-day, Full-Featured Trial
• Highly configurable platform

• QMT support
• Supporting different platforms such as Linux, Solaris, Mac OSX, and BSD
• Offering EZMLM mailing list manager, VERPs, and automatic host configuration
• Having a modular-based system (It allows you to replace any single part of the system with an alternative module)
• Managing custom mailing lists and supporting the automatic prevention of mailing loops
• User-controlled wildcard mailboxes

• Managing calendars, address books, and tasks on a user-friendly web UI or mobile devices
• Easy-to-use web UI to manage folders, emails, and sieve filters
• Antispam and antivirus systems, including SpamAssassin, ClamAV, SPF, etc.
• Storing mail accounts in OpenLDAP, MySQL, MariaDB, and PostgreSQL backends

• JMAP support
• Supporting antivirus and anti-spam toolkits
• Handling deliverability through SPF, DKIM, DMARC
• Using mail filtering
• Full authentication options through Cyrus SASL
• Deploying consistent software updates
• Supporting access control lists on mailboxes

• Using web-based control panel for email configurations and settings
• Contacts and calendar synchronization
• Free TLS (SSL) certificates from Let’s encrypt
• Implementing modern mail protocols (SPF, DKIM, and DMARC) and the latest security practices, including opportunistic TLS, strong ciphers, and HST

• Built-in support for standard web protocols (SMTP, POP3, IMAP, DANE, ActiveSync, and Sieve)
• Central Storage Support and easy integration with directory service and mail delivery systems
• Email filtration based on pre-defined criteria
• Cloud service for using and sharing files between users

It provides users with so many features, such as:

• Group calendars and document sharing
• Mobile web client application
• Suitable for hosting on VPS
• Customizable
• Backup feature
• Email management
• Instant messaging feature

• Shared calendars, contacts, reminders, IMAP files, and tasks
• Supports IMAP, POP3, 3-pane, and 3-column layouts, and HTML messages
• Provides message filtering
• Supports News feed
• Supports mobile email access
• Advanced productivity tools
• Spell-checker
• Email filtration
• Threaded conversation view

• Supports SMTP, LMTP, JMAP, POP3, IMAP, and ManageSieve
• Email management
• Store the message data
• Filtering spam emails

Free SMTP Server Linux

SMTP servers can be used for a variety of purposes, the most common of which is to send and receive emails.

Small businesses and individual users are always looking for free SMTP servers. There are many different SMTP servers for both Windows and Linux available on the internet. Some of them are free, while others charge a fee. The best SMTP server is one that is reliable, fast, and easy to use.

The best SMTP server Linux is undoubtedly Sendmail. Sendmail is very powerful and has many features that other SMTP server applications lack. It’s open-source, feature-rich, and easy to configure. Plus, it’s free!

Open Source Mail Server Linux

Open-source mail servers are becoming more and more popular as businesses and individuals search for ways to cut costs and increase efficiency. But what is an open-source mail server? And why are they becoming so popular?

An open-source mail server is a type of server that uses software that is freely available to the public. This means that the code used to create the software can be modified and improved by anyone who chooses to do so.

An open-source mail server Linux is a great alternative to expensive commercial options. It can be configured to your specific needs, and it’s free! There are many different open-source mail servers available for Linux, so do your research to find the best one for you.

Be sure to evaluate the features that are important to you, such as spam filtering, virus protection, and user support. Once you have chosen a server, be prepared to spend some time configuring it to meet your needs.

There are several reasons why open-source Linux mail servers are becoming so popular:

Wrapping Up — Choosing the Best Linux Mail Server

Choosing any one of the best mail servers for Linux depends on the specific needs of your business, but aside from choosing the best Linux mail server, you should also choose a good Linux VPS hosting provider. Even the best mail servers cannot perform well when your server is down or limited in resources. A decent but affordable VPS is perhaps the best way to start out or even expand to a mid-sized online business.

Here at Cloudzy, our Linux VPS services provide you with robust infrastructure and ultrafast connections, giving you a secure and safe hosting experience at affordable prices. Plus, our next-gen SSD storage with NVMe protocol and DDR4 RAM devices are offered to ensure high performance. We provide services to businesses of any size. We offer Linux VPS in more than 15 global locations with extensive peering and minimal latency.