Microsoft Defender for Office 365 vs Abnormal Security
Side-by-side from the Top 11 ranking of Top 11 Email Security Software. Last verified July 4, 2026.
The short answer
Abnormal Security ranks higher on Top 11 (#1 vs #4) for IT and security leaders. Behavioral AI that stops BEC gateways miss, API-deployed in under an hour.
At a glance
| Microsoft Defender for Office 365 | Abnormal Security | |
|---|---|---|
| Top 11 rank | #4 / Top 11 Email Security Software | #1 / Top 11 Email Security Software |
| Score (out of 9.4) | 8.8 | 9.2 |
| Best for | Best native option for Microsoft 365 | Best overall for BEC and account takeover |
| Pricing | $ ($2/user/mo Plan 1, $5/user/mo Plan 2, or bundled in E5) | $$$ (custom, per-mailbox enterprise pricing) |
| HQ | Redmond, USA | San Francisco, USA |
| Founded | 2015 | 2018 |
Microsoft Defender for Office 365
Native M365 protection, included in E5 at $0 extra.
www.microsoft.com/en-us/security/business/siem-and-xdr/microsoft-defender-office-365Abnormal Security
Behavioral AI that stops BEC gateways miss, API-deployed in under an hour.
abnormalsecurity.comMethodology and scoring weights live at /methodology. No vendor pays for placement — see about.