# Microsoft Defender for Office 365 alternatives: what AI models name instead, October 2026

IT AI Recommendation Index, October 2026 Edition. 118 of the 252 answers in the 1 category where Microsoft Defender for Office 365 holds a standing named it neither first nor as an alternative; these are the first choices those answers made. Page: https://it-ai-index.com/vendors/microsoft-defender-for-office-365/alternatives/

## Named instead, most often (every category and segment added)

- Proofpoint Email Protection: 15
- Abnormal AI: 11
- Check Point Harmony Email & Collaboration: 8
- Mimecast Email Security: 7
- Barracuda Email Protection: 6
- Google Workspace: 3

## Email security

**Small business**: 36 of 84 answers did not name Microsoft Defender for Office 365 (Microsoft Defender for Office 365 is #1 of 10 at 27%).

- Abnormal AI: first choice in 3 of those 36
- Proofpoint Email Protection: first choice in 3 of those 36
- Barracuda Email Protection: first choice in 2 of those 36
- Check Point Harmony Email & Collaboration: first choice in 2 of those 36
- Google Workspace: first choice in 2 of those 36
- Microsoft 365: first choice in 2 of those 36
- Mimecast Email Security: first choice in 2 of those 36
- Huntress Email Security: first choice in 1 of those 36

**Mid-market**: 42 of 84 answers did not name Microsoft Defender for Office 365 (Microsoft Defender for Office 365 is #1 of 9 at 32%).

- Check Point Harmony Email & Collaboration: first choice in 5 of those 42
- Barracuda Email Protection: first choice in 4 of those 42
- Abnormal AI: first choice in 3 of those 42
- Mimecast Email Security: first choice in 3 of those 42
- SpamTitan: first choice in 3 of those 42
- IRONSCALES: first choice in 2 of those 42
- Proofpoint Email Protection: first choice in 2 of those 42
- Sublime Security: first choice in 2 of those 42

**Enterprise**: 40 of 84 answers did not name Microsoft Defender for Office 365 (Microsoft Defender for Office 365 is #2 of 8 at 29%).

- Proofpoint Email Protection: first choice in 10 of those 40
- Abnormal AI: first choice in 5 of those 40
- Mimecast Email Security: first choice in 2 of those 40
- API-Based Integrated Email Cloud Security: first choice in 1 of those 40
- Check Point Harmony Email & Collaboration: first choice in 1 of those 40
- Google Workspace: first choice in 1 of those 40
- Native Microsoft 365: first choice in 1 of those 40

Published under CC BY 4.0. The output is the models' output; nothing here is a recommendation by the index.