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Microsoft Defender for Office 365
5
154
4
70
3
8
2
5
1
1
Based on GetApp‘s extensive, proprietary database of in-depth, verified user reviews
Cloud-based email security and threat management software
Last updated: March 2026
Microsoft Defender for Office 365 Alternatives & Competitors (2026)
Top 1 free alternatives
Heimdal Email Security
Email Protection in a Redefined Spam Filter
0.5
Value for money
No pricing info
Starting price
No pricing info
0.5
Functionality
Allow/Block List
5/5
Archiving & Retention
4/5
Active Directory Integration
N/A
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
Trustifi
Protect Your Business Emails with AI-Powered Security
0.4
Value for money
Starting price
No pricing info
0.3
Functionality
Alerts/Escalation
5/5
Allow/Block List
5/5
Active Directory Integration
N/A
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
Libraesva Email Security
Exceptional Email Security
0.4
Value for money
Starting price
No pricing info
0.3
Functionality
Anomaly/Malware Detection
4.7/5
Active Directory Integration
N/A
Activity Dashboard
N/A
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
Hoxhunt
Make security training engaging, personalized, and effective
0.3
Value for money
No pricing info
Starting price
No pricing info
0.3
Functionality
Assessment Management
5/5
Alerts/Notifications
4.7/5
Activity Dashboard
4.7/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.1
Value for money
Starting price
No pricing info
0.1
Functionality
Anomaly/Malware Detection
4.7/5
Anti Virus
4.7/5
Activity Monitoring
4.6/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
Value for money
Starting price
No pricing info
0.1
Functionality
Allow/Block List
4.5/5
Activity Dashboard
4.5/5
Access Controls/Permissions
4/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.4
Value for money
No pricing info
Starting price
No pricing info
0.1
Functionality
Email Attachment Protection
5/5
Email Filtering
5/5
Allow/Block List
4.5/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.2
Value for money
Starting price
No pricing info
0.2
Functionality
Email Attachment Protection
4.5/5
Email Management
4.4/5
Email Filtering
4.3/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.3
Value for money
No pricing info
Starting price
No pricing info
0.2
Functionality
Email Attachment Protection
4.9/5
Anomaly/Malware Detection
4.8/5
Archiving & Retention
4.8/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.4
Value for money
Starting price
No pricing info
0.4
Functionality
Activity Dashboard
5/5
Alerts/Escalation
5/5
Allow/Block List
5/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.2
Value for money
Starting price
No pricing info
0.3
Functionality
Activity Dashboard
5/5
Activity Dashboard
N/A
AI/Machine Learning
N/A
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.5
Value for money
No pricing info
Starting price
No pricing info
0.5
Functionality
Activity Dashboard
5/5
Alerts/Notifications
5/5
Anomaly/Malware Detection
5/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.4
Value for money
No pricing info
Starting price
No pricing info
0.2
Functionality
Anti Spam
5/5
Anti Virus
4.7/5
Anomaly/Malware Detection
4.5/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.3
Value for money
Starting price
No pricing info
0.4
Functionality
Email Attachment Protection
4.8/5
Allow/Block List
4.3/5
AI/Machine Learning
N/A
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.4
Value for money
Starting price
No pricing info
0.4
Functionality
Activity Dashboard
5/5
AI/Machine Learning
5/5
Alerts/Escalation
5/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.1
Value for money
Starting price
No pricing info
0.1
Functionality
Allow/Block List
5/5
Archiving & Retention
5/5
Anomaly/Malware Detection
4/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.4
Value for money
No pricing info
Starting price
No pricing info
0.1
Functionality
Allow/Block List
5/5
Archiving & Retention
5/5
Active Directory Integration
N/A
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.3
Value for money
No pricing info
Starting price
No pricing info
0.2
Functionality
Anti Spam
4.7/5
Anomaly/Malware Detection
4/5
API
4/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
0.5
Value for money
No pricing info
Starting price
No pricing info
0.5
Functionality
Alerts/Escalation
5/5
Anomaly/Malware Detection
4.5/5
Anti Virus
4/5
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5
4.5
Value for money
No pricing info
Starting price
No pricing info
4.5
Functionality
Active Directory Integration
N/A
Activity Dashboard
N/A
Alerts/Notifications
N/A
Top Features
Allow/Block List
4.5/5
Email Attachment Protection
4.5/5
Alerts/Escalation
4.4/5