mailcow vs Nullmailer
A side-by-side comparison of two self-hosted mail servers options
— licensing, setup difficulty, resource needs, and what each one
replaces.
Not the right match-up?
Compare mailcow with
choose an app… listmonk Docker Mailserver Mailspring Postal MailHog Mail-in-a-Box Stalwart Mail Server Mautic Mailpit Mailpile Mailu Roundcube Himalaya SimpleLogin MailCatcher Maddy Mail Server Mox Mailtrain Haraka AnonAddy RainLoop imapsync smtp4dev NeoMutt Modoboa aerc Dittofeed Rspamd Keila emailwiz SendPortal SOGo WildDuck Mailvelope iRedMail Cypht SnappyMail Forward Email Cuttlefish DebOps swaks parsedmarc Cozy PostfixAdmin Dovecot Nextcloud Groupware Apache James Nextcloud Mail chasquid Sup Betterbird imapfilter OpenTrashmail notmuch Sieve Editor meli phpList Exim alot alps Lieer Cyrus IMAP OfflineIMAP Larch OpenSMTPD Postfix ViMbAdmin Chatmail Mailman isync MailWhale Afterlogic WebMail Lite afew Apache SpamAssassin Sympa Simple NixOS Mailserver EGroupware msmtp fdm Group-Office DragonFly Mail Agent Horde Groupware Claws Mail Fetchmail DAViCal HyperKitty Kolab Groupware piler Postorius getmail6 OpenDMARC OpenDKIM bogofilter Citadel Schleuder Dovecot Pigeonhole Kopano Groupware Core Tine DKIMpy Milter mpop Courier Mail Server Afterlogic DAV b1gMail Dovel EmailRelay Inboxen Sendmail Sendy SquirrelMail
Compare Nullmailer with
choose an app… listmonk Docker Mailserver Mailspring Postal MailHog Mail-in-a-Box Stalwart Mail Server Mautic Mailpit OpenSMTPD msmtp DragonFly Mail Agent
Feature mailcow Nullmailer Category Mail Servers Mail Servers License GPL-3.0 GPL-2.0 Language JavaScript C++ Setup difficulty Medium Easy Min. RAM 6,144 MB 16 MB Deployment docker bare-metal, source GitHub stars ★ 13,245 ★ 199 First released 2016 2000 Replaces Microsoft Exchange, Google Workspace Sendmail
Why pick each one
Choose mailcow if… All components preconfigured Active community mailcow details
Frequently asked questions Is mailcow or Nullmailer better? Neither is universally better. mailcow has the larger community, while Nullmailer is simpler to set up (easy difficulty). Choose based on the comparison table above and your own setup.
Are mailcow and Nullmailer free and open-source? Yes. mailcow is licensed under GPL-3.0 and Nullmailer under GPL-2.0. Both can be self-hosted at no software cost.
Can I run mailcow and Nullmailer with Docker? mailcow: yes. Nullmailer: check the project docs for container support.