Microsoft Defender for Office 365 review
Native M365 protection, included in E5 at $0 extra.
Top 11 rank
#4 of 11
Score
8.8/9.4
Pricing
$ ($2/user/mo Plan 1, $5/user/mo Plan 2, or bundled in E5)
HQ
Redmond, USA
Verdict
Microsoft Defender for Office 365 ranks fourth because it is built into the platform most companies already run, with Safe Links, Safe Attachments, and automated investigation included in E5 at no extra vendor cost.
What customers praise
Automated investigation and response ties email alerts to the wider Defender XDR signal, which shortens triage for teams already on Microsoft security.
What customers criticise
Native filtering lets more novel phishing through than specialist tools, so many firms still layer a third-party product on top.
Best for
Microsoft 365 shops that want native protection without adding a third-party vendor.
At a glance
- Integrations: Microsoft 365, Microsoft Sentinel, Microsoft Defender XDR, Entra ID
- Compliance: SOC 2 Type II, ISO 27001, HIPAA, FedRAMP
- Regions served: North America, EMEA, APAC
- Typical onboarding: 1 day
Red flags
Public risk signals as of July 2026: none. No material public risk signals as of 2026-07-04. See the full red-flag report.
Alternatives
See alternatives to Microsoft Defender for Office 365, or compare against the next-ranked entry: Microsoft Defender for Office 365 vs Barracuda Email Protection.
Source: Top 11 Top 11 Email Security Software, verified July 4, 2026 — no paid placement.