Microsoft Defender for Office 365 vs Cisco Secure Email Threat Defense
Side-by-side from the Top 11 ranking of Abnormal Security vs Proofpoint vs Mimecast: 11 Best Email Security Software 2026. Last verified July 4, 2026.
The short answer
Microsoft Defender for Office 365 ranks higher on Top 11 (#4 vs #6) for IT and security leaders. Native M365 protection, included in E5 at $0 extra.
At a glance
| Microsoft Defender for Office 365 | Cisco Secure Email Threat Defense | |
|---|---|---|
| Top 11 rank | #4 / Abnormal Security vs Proofpoint vs Mimecast: 11 Best Email Security Software 2026 | #6 / Abnormal Security vs Proofpoint vs Mimecast: 11 Best Email Security Software 2026 |
| Score (out of 9.4) | 8.8 | 8.5 |
| Best for | Best native option for Microsoft 365 | Best for existing Cisco security shops |
| Pricing | $ ($2/user/mo Plan 1, $5/user/mo Plan 2, or bundled in E5) | $$$ (custom, per-user enterprise pricing) |
| HQ | Redmond, USA | San Jose, USA |
| Founded | 2015 | 1984 |
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-365See full entry in Abnormal Security vs Proofpoint vs Mimecast: 11 Best Email Security Software 2026
Cisco Secure Email Threat Defense
Talos-backed detection wired into the Cisco stack.
www.cisco.com/site/us/en/products/security/secure-email/index.htmlSee full entry in Abnormal Security vs Proofpoint vs Mimecast: 11 Best Email Security Software 2026
Methodology and scoring weights live at /methodology. No vendor pays for placement — see about.