Mail-in-a-Box vs Citadel
A side-by-side comparison of two self-hosted apps from related categories
— licensing, setup difficulty, resource needs, and what each one
replaces.
Not the right match-up?
Compare Mail-in-a-Box with
choose an app… Nextcloud listmonk Docker Mailserver Mailspring Postal MailHog Stalwart Mail Server mailcow Mautic Mailpit Mailpile CryptPad Mailu Roundcube Himalaya SimpleLogin ONLYOFFICE Docs MailCatcher Maddy Mail Server Mox Mailtrain Haraka AnonAddy RainLoop imapsync smtp4dev NeoMutt Modoboa Collabora Online aerc OnlyOffice Community Server 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 LibreOffice Online Lieer Cyrus IMAP OfflineIMAP Larch OpenSMTPD Postfix ViMbAdmin Chatmail Mailman isync MailWhale Afterlogic WebMail Lite afew Apache SpamAssassin Sympa Simple NixOS Mailserver Calligra Suite EGroupware msmtp fdm Group-Office DragonFly Mail Agent Claws Mail Fetchmail HyperKitty piler Postorius Nullmailer getmail6 OpenDMARC OpenDKIM bogofilter Schleuder Dovecot Pigeonhole Tine DKIMpy Milter mpop Courier Mail Server Afterlogic DAV b1gMail Dovel EmailRelay Inboxen Sendmail Sendy SquirrelMail
Compare Citadel with
choose an app… Calcom Calendar Nextcloud Docker Mailserver Stalwart Mail Server mailcow CryptPad Mailu ONLYOFFICE Docs Maddy Mail Server Mox Rallly Colanode Radicale Easy!Appointments Collabora Online Baïkal OnlyOffice Community Server SOGo WildDuck Twake Workplace iRedMail ZenTao Nextcloud Deck Cozy Dovecot Nextcloud Groupware Apache James Twake Drive Exim Davis Openmeetings LibreOffice Online Cyrus IMAP Postfix Calligra Suite EGroupware Group-Office Horde Groupware DAViCal Kolab Groupware Kontact Feng Office Kopano Groupware Core Tine Courier Mail Server Cozy Contacts
Feature Mail-in-a-Box Citadel Category Mail Servers Groupware License CC0-1.0 GPL-3.0 Language Python C Setup difficulty Easy Medium Min. RAM 1,024 MB 512 MB Deployment bare-metal, one-click bare-metal, source GitHub stars ★ 15,385 ★ 100 First released 2014 1987 Replaces Google Workspace, Microsoft 365 Microsoft Exchange, Microsoft 365
Frequently asked questions Is Mail-in-a-Box or Citadel better? Mail-in-a-Box is the stronger all-round pick: it has both the larger community and the simpler easy setup. Consider Citadel if its specific feature set fits your needs better.
Are Mail-in-a-Box and Citadel free and open-source? Yes. Mail-in-a-Box is licensed under CC0-1.0 and Citadel under GPL-3.0. Both can be self-hosted at no software cost.
Can I run Mail-in-a-Box and Citadel with Docker? Mail-in-a-Box: check the project docs for container support. Citadel: check the project docs for container support.