Microsoft Defender for Office 365 vs Sophos Email: Side-by-Side Comparison (2026)

Microsoft Defender for Office 365

Mid-market and enterprise teams already operating Microsoft 365 should standardize on Defender for Office 365 because the integration depth eliminates the detection gaps that plague bolt-on email security tools, particularly in Teams and SharePoint where most modern attacks now land. The platform's automated Business Email Compromise disruption with user disabling and device isolation actually stops lateral movement in real time rather than just flagging suspicious mail. Skip this if your organization runs primarily on Gmail or Slack; the advantage collapses outside the Microsoft ecosystem, and you'll find cheaper, more agile options elsewhere.

Sophos Email

Mid-market and enterprise teams already running Sophos endpoint or MDR will extract real value from Sophos Email because the threat intelligence flows both directions, catching BEC and supply-chain phishing that isolated email gateways miss. The 20+ ML models and native integration with Sophos X-Ops means suspicious emails trigger endpoint investigations automatically without manual handoffs. Skip this if your organization needs email security completely decoupled from your endpoint vendor, or if you're heavily invested in a non-Sophos EDR and want to avoid vendor consolidation.