Microsoft Exchange Online vs mailcow

Microsoft Exchange Online9.3Visit mailcow8.5Visit

Higher score Microsoft Exchange Online #1 in Mail Server Software 9.3/10 Paid ✓ 0 of 5 features Visit Microsoft

vs

mailcow #7 in Mail Server Software 8.5/10 Free plan Free plan✓ 0 of 5 features Visit mailcow

• Microsoft Exchange Online fits best

  Microsoft-centric business email

• mailcow fits best

  Docker-based mail and groupware deployments

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Side by side

Feature	Microsoft Exchange Online 9.3/10 Visit ↗	mailcow 8.5/10 Visit ↗
At a glance
Editor score	9.3	8.5
Ranking	#1 in Mail Server Software	#7 in Mail Server Software
Best for	Microsoft-centric business email	Docker-based mail and groupware deployments
Pricing model	Paid	Free
Starting price	—	Free plan
Free plan	—	✓ (best)
Free trial	—	—
Deployment	Cloud, Browser extension	Self-hosted, Cloud
Platforms	Web, Windows, macOS, iOS, Android	Web, Linux
Support	Phone, Docs · 24/7	Community, Docs, Email
Integrations	2 integrations	5 integrations
Built for	Small business, Mid-market, Enterprise	Solo, Small business, Mid-market, Enterprise
Features Microsoft Exchange Online 0/5 · mailcow 0/5
Webmail interface	Not checked yet	Not checked yet
IMAP/POP3 access	Not checked yet	Not checked yet
Mobile sync	Not checked yet	Not checked yet
Antispam tools	Not checked yet	Not checked yet
High availability	Not checked yet	Not checked yet
Specs
License model	Not checked yet	Not checked yet
Mailbox limit	Not checked yet	Not checked yet
Our review
Pros	Outlook access across web, desktop, and mobile platforms Spam filtering, archiving, DLP, and compliance features Migration support for Exchange, IMAP, PST, and other systems	Includes Dovecot, SOGo, Rspamd, ClamAV and MariaDB components Supports TOTP, YubiKey OTP and WebAuthn two-factor authentication Provides mailbox migration tools and configurable message limits
Cons	Paid access is required for every mailbox Plan 1 limits primary mailbox storage to 50 GB Some archive capabilities depend on licensing and admin enablement	Requires self-hosted infrastructure and administrator-managed operations Its platform model is limited to self-hosted deployments The component-rich stack requires familiarity with mail infrastructure
Our verdict	Microsoft Exchange Online is a cloud-hosted business email and calendaring service for organizations that want custom-domain mailboxes alongside Outlook access. It supports email, calendars, contacts, shared mailboxes, browser access,… Read the review →	mailcow: dockerized is an open-source email and groupware suite packaged with Docker. It is intended for individuals, small businesses and organizations that want to manage their own email infrastructure rather than subscribe to a… Read the review →

Strengths and trade-offs

• Microsoft Exchange Online — where it wins

  • Outlook access across web, desktop, and mobile platforms
  • Spam filtering, archiving, DLP, and compliance features
  • Migration support for Exchange, IMAP, PST, and other systems

  Where it doesn't

  • Paid access is required for every mailbox
  • Plan 1 limits primary mailbox storage to 50 GB
  • Some archive capabilities depend on licensing and admin enablement

• mailcow — where it wins

  • Includes Dovecot, SOGo, Rspamd, ClamAV and MariaDB components
  • Supports TOTP, YubiKey OTP and WebAuthn two-factor authentication
  • Provides mailbox migration tools and configurable message limits

  Where it doesn't

  • Requires self-hosted infrastructure and administrator-managed operations
  • Its platform model is limited to self-hosted deployments
  • The component-rich stack requires familiarity with mail infrastructure

• Microsoft Exchange Online9.3/10 · Paid

  A Microsoft-centric hosted mailbox service with Outlook, archiving, compliance, and migration tools.

  Visit MicrosoftFull verdict →
• mailcow8.5/10 · Free plan

  A Dockerized mail and groupware suite for teams managing their own infrastructure.

  Visit mailcowFull verdict →