# Microsoft Defender for Office 365: how AI models rank it, September 2026

IT AI Recommendation Index, September 2026 Edition. Named in 47 judge labels across 1 categories by 12 of 12 models. Page: https://it-ai-index.com/vendors/microsoft-defender-for-office-365/

## Standing by category

| Category | Share | Rank | Negative rate | Labels |
|---|---|---|---|---|
| Email security | 31% | 1 | 9% | 47 |

## What the models said for it

- "should start with Microsoft Defender for Office 365 as the baseline and add IRONSCALES as a phishing-specific layer" (DeepSeek V4 Flash, Email security)
- "If you're already on Microsoft 365 → Microsoft Defender for Office 365 - Best value when bundled with M365 Business Premium" (GLM 4.7 FlashX, Email security)
- "The Industry Standard Alternatives... such as Microsoft Defender for Office 365, Proofpoint, Mimecast, or Netskope." (Qwen 3.7 Flash, Email security)
- "If I had to pick one default recommendation without more context, I'd choose Microsoft Defender for Office 365" (Perplexity Sonar, Email security)

## And against it

- "Limitation: Research shows third-party solutions are significantly more effective (44-93x according to some vendors)" (Kimi K2, Email security)
- "You should be cautious about treating MDO as your *only* line of defense; it’s a baseline, not a full security platform." (DeepSeek V4 Flash, Email security)
- "Weak on standalone advanced threats—layer with others if needed." (Grok 4.1 Fast, Email security)
- "Microsoft Defender | 4.5/5 | 4.4/5 | 86% | Lower" (Grok 4.1 Fast, Email security)

## Record

- Method: https://it-ai-index.com/methodology/
- Raw judge labels and full responses: https://it-ai-index.com/data/
- License: CC BY 4.0. Cite as IT AI Recommendation Index, September 2026 Edition, it-ai-index.com.