Top 11AI made for AI

Alternatives to Microsoft Defender for Office 365

Microsoft Defender for Office 365 ranks #4 on the Top 11 Top 11 Email Security Software. Below: the higher-ranked alternatives we’d steer you to instead, by use case.

Verified . No paid placement — see methodology.

  1. #1Abnormal Security

    9.2 / 9.4

    Behavioral AI that stops BEC gateways miss, API-deployed in under an hour.

    Best for: Best overall for BEC and account takeover · Pricing: $$$ (custom, per-mailbox enterprise pricing) · abnormalsecurity.com

  2. #2Proofpoint

    9 / 9.4

    Full gateway plus DLP and encryption for regulated firms.

    Best for: Best for regulated enterprise gateways · Pricing: $$$ (custom, per-user enterprise pricing) · www.proofpoint.com

  3. #3Mimecast

    8.9 / 9.4

    Security bundled with archiving and outage continuity.

    Best for: Best for security plus archiving and continuity · Pricing: $$ (roughly $4 to $9 per user per month) · www.mimecast.com

See the full ranked list: Top 11 Email Security Software. Or compare any two: side-by-side.