Microsoft Defender for Office 365 vs Fortinet FortiMail
Side-by-side from the Top 11 ranking of Top 11 Email Security Software. Last verified July 4, 2026.
The short answer
Microsoft Defender for Office 365 ranks higher on Top 11 (#4 vs #8) for IT and security leaders. Native M365 protection, included in E5 at $0 extra.
At a glance
| Microsoft Defender for Office 365 | Fortinet FortiMail | |
|---|---|---|
| Top 11 rank | #4 / Top 11 Email Security Software | #8 / Top 11 Email Security Software |
| Score (out of 9.4) | 8.8 | 8.3 |
| Best for | Best native option for Microsoft 365 | Best for flexible gateway deployment |
| Pricing | $ ($2/user/mo Plan 1, $5/user/mo Plan 2, or bundled in E5) | $$ (appliance or per-user cloud, custom) |
| HQ | Redmond, USA | Sunnyvale, USA |
| Founded | 2015 | 2000 |
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-365Fortinet FortiMail
Flexible gateway wired into the Fortinet Security Fabric.
www.fortinet.com/products/email-securityMethodology and scoring weights live at /methodology. No vendor pays for placement — see about.