Communication·Standings

Email Server Software

Email server software sends, receives and manages mail; the choice turns on where you can run it and whether its price fits your setup.

Use the signal score out of 10 as a quick comparison. The board also marks a public API, open-source code and a free tier, so you can check those needs directly.

• 33 platforms
• 2 with a public API on this page
• 24 with a free tier
• Checked 24 Oct 2026

1. #PlatformSignalPlugs inPrice
2. 1
   A

   Axigenaxigen.com

   Email, calendar, and collaboration server with a free edition for home or small-business use.

   6.4 APIOpenFree Free tier
   →
3. 2
   M

   mailcowmailcow.email

   Free open-source Docker software for email, with a web interface for managing domains and addresses.

   6.4 APIOpenFree Free tier · from €8.90/mo
   →
4. 3
   M

   MailEnablemailenable.com

   Windows messaging software with a free edition and paid options starting at $395.

   6.3 APIOpenFree Free tier · $395 one-time
   →
5. 4
   S

   SmarterMailsmartertools.com

   Email and collaboration server offers calendars, chat, meetings, and a free plan.

   6.3 APIOpenFree Free tier · from $500/yr
   →
6. 5
   SM

   Stalwart Mail Serverstalwart.email

   Open-source mail and collaboration server supports email, calendars, contacts, and shared files.

   6.3 APIOpenFree Free tier · from $1.09/yr
   →
7. 6
   I

   iRedMailiredmail.org

   iRedMail is open-source software for deploying a full-featured mail server.

   6.2 APIOpenFree Free tier · from $10/yr
   →
8. 7
   M

   Mailumailu.io

   Free software packaged as Docker images, with email attachment search and domain aliases.

   6.2 APIOpenFree Free tier
   →
9. 8
   E

   Eximexim.org

   Exim is a mail transfer agent for hosts running Unix or Unix-like operating systems.

   6.2 APIOpenFree Free tier
   →
10. 9
    MI

    Mail-in-a-Boxmailinabox.email

    Free open-source software that sets up a cloud computer for email, calendar syncing, and mail filtering.

    6.1 APIOpenFree Free tier
    →
11. 10
    P

    Postfixpostfix.org

    Free mail server for UNIX-like systems supports encrypted and authenticated SMTP connections.

    6.1 APIOpenFree Free tier
    →
12. 11
    M

    Modoboamodoboa.org

    Open-source server software includes webmail, calendars, address books, and mailbox controls.

    6.1 APIOpenFree Free tier · from €139/yr
    →
13. 12
    DM

    Docker Mailserverdocker-mailserver.github.io

    Docker Mailserver is a production-ready full-stack mail server providing SMTP, IMAP, LDAP, anti-spam and anti-virus in a container.

    6.0 APIOpenFree Free tier
    →
14. 13
    PM

    Pegasus Mailpmail.com

    Free, offline email client for Windows supports one or multiple users on a computer or local network.

    6.0 APIOpenFree Free tier
    →
15. 14
    H

    hMailServerhmailserver.com

    Free self-hosted server for SMTP, IMAP, POP3, webmail, spam filtering, and ClamAV scanning.

    6.0 APIOpenFree Free tier
    →
16. 15
    PI

    poste.ioposte.io

    Self-hosted mail server bundles webmail, spam protection, and mail services in one Docker container.

    6.0 APIOpenFree Free tier · from $349/yr
    →
17. 16
    ZC

    Zimbra Collaborationzimbra.com

    Email and collaboration suite includes calendars, contacts, tasks, and file sharing.

    6.0 APIOpenFree Free tier
    →
18. 17
    CI

    Cyrus IMAPcyrusimap.org

    Cyrus IMAP is an email, contacts, and calendar server.

    5.9 APIOpenFree Free tier
    →
19. 18
    MM

    Maddy Mail Servermaddy.email

    Linux mail daemon combining SMTP, IMAP storage, and DKIM, SPF, DMARC, and other security protocols.

    5.9 APIOpenFree Free tier
    →
20. 19
    AJ

    Apache Jamesjames.apache.org

    Modular JVM mail server with SMTP, IMAP, POP3, JMAP, filtering, and routing controls.

    5.9 APIOpenFree Free tier
    →
21. 20
    D

    Dovecotdovecot.org

    Free Linux mail server with IMAP, POP3, LMTP, indexing, caching, and Sieve filtering.

    5.8 APIOpenFree Free tier
    →
22. 21
    ME

    Microsoft Exchange Onlinemicrosoft.com

    Hosted business email with calendars and contacts works across browsers, phones, and computers.

    5.6 APIOpenFree —
    →
23. 22
    G

    grommuniogrommunio.com
    5.6 APIOpenFree Free tier · from €1.99/mo
    →
24. 23
    W

    Whitemailwhitemail.io
    5.1 APIOpenFree Free tier
    →
25. 24
    K

    KumoMTAkumomta.com

    Linux mail transfer software with free community access and paid support sponsorships.

    5.1 APIOpenFree Free tier · from $5,000/yr
    →
26. 25
    SM

    Synology MailPlus Serversynology.com

    Email server software has a free plan and works with web and mobile apps.

    5.1 APIOpenFree Free tier
    →

Places #1, #2, #3, #4, #5 on this board are open to sponsors. Take #1 · Other ways to advertise

How to choose

Which platforms does it need to run on?

Match the server's platform to your setup before comparing features. Listed options span Linux, self-hosting, web, Windows, iOS and macOS.

CommuniGate Pro is listed for Linux, macOS and Windows. Check the platform mark for any tool you are considering.

What will the email server cost?

Prices range from free plans to paid licenses and subscriptions, so check the pricing note rather than assuming a common model.

Examples are EVO Mail Server at $259, GreenArrow Engine On-Premises at $600 per month, grommunio paid plans starting at €1.99 per user per month, and iRedMail paid plans starting at $10 per year. CommuniGate Pro lists pricing on request.

Can I try it before paying?

Look for a free plan or a stated trial when you need a low-risk evaluation. Apache James, Cyrus IMAP, Docker Mailserver, Dovecot, Exim and hMailServer each have a free plan listed.

Axigen has a 60-day trial listed. A free plan and a free trial are different: one can continue without payment, while the other lasts for a stated period.

Do I need an API or open-source code?

Use the board's API and open-source marks to narrow the list when another application must connect to the mail server or your team needs to inspect and change code.

If code access matters, read the licence terms before choosing. If integration matters, confirm that the public API fits the actions your existing apps need.

Questions

What is email server software?

It is software for handling email delivery and mailboxes. The board lets you compare where tools run, pricing and signals such as an API or free tier.

Which email servers have a free plan?

Free plans are listed for Apache James, Axigen, Cyrus IMAP, Docker Mailserver, Dovecot, Exim and hMailServer. Other entries also show free-plan status on the board.

Is there email server software for Windows?

Yes. Windows is one of the platforms represented on the board. CommuniGate Pro is listed for Windows, Linux and macOS.

Which email server has a 60-day trial?

Axigen has a 60-day trial listed and also has a free plan.

How much does GreenArrow Engine On-Premises cost?

Its pricing note says from $600 per month.

Some top positions on this board can be paid placements, standing where they were sold. The facts on each platform are not for sale. How we rank · Disclosure