Cloud Email Security Platforms -- Proofpoint Alternatives
Cloud email security platforms provide email threat protection delivered entirely as SaaS, without requiring on-premises appliances or infrastructure. These platforms integrate natively with cloud email services like Microsoft 365 and Google Workspace, either through inline gateway deployment or API-based connectivity. Cloud email security is the fastest-growing segment of the email security market as organizations move to cloud-native architectures and want security solutions that match their deployment model.
Plan 1 from $2/user/month / Plan 2 from $5/user/month / included in E5
The natural choice for Microsoft 365 environments, especially E5 customers who get it included in their license. Native XDR integration with Microsoft Defender correlates email threats with identity, endpoint, and cloud signals. Best for Microsoft-centric organizations wanting cost-efficient, ecosystem-integrated protection.
Custom pricing / per-user licensing
Cloud-native email security with the innovative Writing Style DNA feature for BEC detection and integration with Trend Micro Vision One XDR. Protects both Microsoft 365 and Google Workspace. Best for organizations using the Trend Micro security ecosystem who want competitive pricing.
Custom pricing / per-user licensing
Cloud-delivered comprehensive email security with the added benefit of email continuity. While also listed under enterprise gateways, Mimecast is fully cloud-native and competes directly with Proofpoint for cloud-first organizations wanting archiving, DLP, and awareness training in one platform.
Microsoft's native email security for Microsoft 365 with XDR integration
Plan 1 from $2/user/month / Plan 2 from $5/user/month / included in E5
Microsoft 365-centric organizations wanting native email security with XDR integration and cost efficiency through E5 licensing
Cloud email security gateway with AI-powered BEC detection and XDR integration
Custom pricing / per-user licensing
Organizations wanting capable email security integrated with Trend Micro's broader Vision One XDR platform
Cloud email security platform with threat protection, archiving, and continuity
Custom pricing / per-user licensing
Mid-to-large enterprises wanting a unified email security, archiving, and continuity platform with strong API integrations
Compare all 3 Proofpoint alternatives side-by-side across pricing, deployment, and key capabilities.
| Feature | Microsoft Defender for Office 365 4.4/5 | Trend Micro Email Security 4.1/5 | Mimecast 4.3/5 |
|---|---|---|---|
| Pricing Model | Per-user subscription (bundled with Microsoft 365 E5) | Per-user subscription | Per-user subscription |
| Open Source | -- | -- | -- |
| Cloud-Hosted | + | + | + |
| Self-Hosted | -- | -- | -- |
| Best For | Microsoft 365-centric organizations wanting native email security with XDR integration and cost efficiency through E5 licensing | Organizations wanting capable email security integrated with Trend Micro's broader Vision One XDR platform | Mid-to-large enterprises wanting a unified email security, archiving, and continuity platform with strong API integrations |
| Key Features |
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| Website | Visit | Visit | Visit |
For many organizations, particularly those with Microsoft 365 E5 licensing, Defender for Office 365 provides sufficient protection and eliminates the cost of a separate gateway. Microsoft has invested heavily in its email security capabilities and the native XDR integration is a genuine advantage. However, Proofpoint still leads in detection of advanced, targeted threats — particularly sophisticated BEC campaigns and novel phishing attacks. Organizations in high-risk industries or those facing nation-state threats generally benefit from Proofpoint's superior detection and threat intelligence.
Microsoft Defender for Office 365 only protects Microsoft 365 environments. For Google Workspace protection, Trend Micro Email Security and Mimecast both offer cloud-native integration. Abnormal Security and IRONSCALES also protect Google Workspace via API. If you use Google Workspace, your primary cloud email security options are Trend Micro, Mimecast, or an API-based solution like Abnormal Security — Proofpoint also supports Google Workspace through its gateway deployment.
XDR integration allows email security to correlate threats across email, identity, endpoint, and cloud domains. For example, Microsoft Defender for Office 365 can detect that a phishing email arrived, the user clicked the link, credentials were entered on a fake page, and a suspicious sign-in occurred from a new location — automatically triggering remediation across all layers. Proofpoint achieves similar correlation through API integrations with third-party XDR platforms, but native integration in the Microsoft and Trend Micro ecosystems provides tighter, faster cross-domain response.
Microsoft 365 and Google Workspace include baseline email security, but it historically has not matched the detection efficacy of dedicated email security platforms. Microsoft Defender for Office 365 Plan 2 has closed much of this gap for Microsoft environments. The decision depends on your threat landscape: if you face standard phishing and malware, your provider's built-in security (especially Microsoft E5) may suffice. If you face advanced targeted attacks, BEC, or need archiving and compliance, a dedicated platform like Proofpoint provides demonstrably better protection.
Microsoft's native email security for Microsoft 365 with XDR integration
ComparisonCloud email security gateway with AI-powered BEC detection and XDR integration
ComparisonCloud email security platform with threat protection, archiving, and continuity
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