Best Email Security Tools for 2026

The best email security tools detect the attacks native filters miss, contain compromised accounts, and remediate threats quickly, without adding work for lean teams. This guide gives a framework for evaluating the top email security software for Google Workspace and Microsoft 365, then reviews the leading options against the same criteria. Material protects email for teams at Figma, Gusto, Lyft, and PagerDuty, and every tool below is measured the same way.

What Email Security Tools Do

Email is the most common initial access path for modern breaches, including phishing, impersonation and business email compromise (BEC), malicious URLs, and account takeover (ATO). A strong email security tool does more than block spam. It detects sophisticated social engineering, contains post-delivery and post-compromise risk, and makes remediation fast across every mailbox. Modernize your approach to email security.

How to Choose an Email Security Tool

Six criteria separate a capable email security platform from a basic spam filter. Weigh each against your environment and the size of your team. How to choose an email security solution covers this in more depth.

Coverage

1. Phishing
2. BEC/impersonation
3. URL/attachment threats
4. Internal/outbound threats
5. User-reported email workflows

ATO Resilience

1. Ability to detect suspicious mailbox activity (rules, forwarding, OAuth apps, etc.)
2. Protection of sensitive email data
3. Reduction of blast radius after compromise

Deployment Model

1. Secure email gateway (SEG)
2. API-based
3. Hybrid

Operational Load

1. Tuning requirements
2. False positives
3. User-reported email volume
4. Speed of remediation across mailboxes

Ecosystem Fit

1. Microsoft 365 support
2. Google Workspace support
3. SIEM/SOAR integrations for automation

DMARC and Domain Protection Ownership

1. Whether DMARC management is required
2. Whether it is handled in-product or through a dedicated DMARC tool

Material Security

Best For

Security teams on Google Workspace or Microsoft 365 that want a complete approach to email security: stopping sophisticated inbound attacks and containing account takeovers with automated remediation and context across the cloud office.

What It Is

Material treats email security as more than inbound blocking. It combines detection for advanced attacks with account takeover containment and automated response, correlating the initial email with what happens next, such as mailbox rules, Drive access, and downloads.

Key Capabilities

• Stops VIP impersonation, BEC, and attacks that bypass native defenses
• Contains email account takeovers by protecting sensitive email data and applying behavioral analysis with automated remediation
• API-based deployment for Google Workspace and Microsoft 365 with no network changes
• Detection and response that continues inside the environment, covering risky rules, unsanctioned apps, and misconfigurations
• Also secures files across Google Drive and Microsoft 365, where 57 percent of shared drive data is typically sensitive, and hardens account security to limit what an attacker can reach if a message does get through
• Automated user report response clusters every variant of a reported message and remediates it, cutting phishing triage by up to 91 percent at Gusto

Considerations

Material's depth is strongest in Google Workspace, and its model extends past inbound filtering, so a team that only wants a perimeter spam filter will not use the full platform. It also protects files and identity, which is more than an email-only tool provides.

Final Thoughts

Material is a Google Workspace and Microsoft 365 security platform that stops advanced email threats, contains account takeovers, and protects data across the cloud office with API deployment and automated remediation across the full incident lifecycle.

Proofpoint

Best For

Large organizations that want a mature secure email gateway with broad threat protection and ecosystem depth, especially when DMARC and domain protection are hard requirements.

What It Is

Proofpoint Email Protection is a secure email gateway focused on blocking malicious payloads, URLs, and impersonation-style attacks, including BEC.

Key Capabilities

• BEC and impersonation analysis using AI and signals like header mismatches and DMARC feedback
• URL rewriting with click-time inspection, sandboxing, and browser isolation
• Post-delivery actions such as moving newly identified malicious messages to quarantine

Considerations

Gateway-centric programs can struggle with what happens after a phish succeeds, such as mailbox rules, access, and data movement, which often needs additional tools. See Material vs. Proofpoint.

Final Thoughts

Proofpoint is a mature, enterprise-grade secure email gateway focused on blocking inbound threats and impersonation, with click-time URL protection and post-delivery quarantine.

Abnormal AI (formerly Abnormal Security)

Best For

Teams that prioritize behavioral detection for socially engineered attacks like BEC and vendor fraud and want API-based deployment with automation.

What It Is

Abnormal AI is an API-integrated platform that builds behavioral models to detect anomalies and automate remediation for socially engineered email threats. The company rebranded from Abnormal Security in April 2025.

Key Capabilities

• Behavioral modeling that analyzes identity, relationship, and behavior signals to detect targeted BEC and phishing
• API integration for Microsoft 365 and Google Workspace
• Automated detection and remediation to reduce triage workload

Considerations

If you need message-level access controls and data protection inside the mailbox after compromise, confirm what exists beyond detection and removal. Abnormal's coverage centers on email rather than files and identity. See Material vs. Abnormal AI.

Final Thoughts

Abnormal AI is an API-based email security platform focused on behavioral detection of socially engineered attacks with automated remediation and fast deployment.

Mimecast

Best For

Organizations that want a cloud-native secure email gateway with policy controls and broad protection for Microsoft 365 or Google Workspace.

What It Is

Mimecast's Email Security Cloud Gateway is a cloud-native SEG built to manage complex email environments and add protection beyond native controls.

Key Capabilities

• Secure email gateway approach with AI and ML detection
• Configurable policies and granular controls
• Deployment with or without a gateway

Considerations

To reduce team workload, validate automation depth: user-reported message handling, org-wide remediation speed, and how DMARC validation interacts with your tenant settings. See Material vs. Mimecast.

Final Thoughts

Mimecast is a cloud-native secure email gateway for Microsoft 365 and Google Workspace with AI detection and flexible deployment, though day-two operations should be tested in your environment.

Barracuda

Best For

Teams that want a straightforward cloud email protection suite with layered defenses and incident response options.

What It Is

Barracuda Email Protection combines spam and malware defense, phishing and impersonation protection, sandboxing, link protection, and incident response.

Key Capabilities

• Advanced threat protection with sandboxing for suspicious attachments
• Link protection with click-time analysis
• Anomaly-based impersonation and BEC detection
• Incident response to remediate messages across mailboxes

Considerations

If account takeover and data access after compromise are your biggest risks, confirm how deeply it correlates mailbox behavior, identity signals, and sensitive data exposure rather than message-level filtering alone.

Final Thoughts

Barracuda Email Protection is a cloud suite layering spam and malware defense, sandboxing, link protection, impersonation detection, and incident response.

Avanan (Check Point Harmony Email and Collaboration)

Best For

Cloud-first teams that want API-based email security with unified quarantine and collaboration app coverage under the Check Point platform.

What It Is

Avanan is sold as Check Point Harmony Email and Collaboration, a cloud-first email security product with unified quarantine and DMARC monitoring.

Key Capabilities

• Unified quarantine across native and vendor quarantine
• DMARC monitoring for impersonation defense
• User-reporting workflow integrations

Considerations

Harmony fits well if you already standardize on Check Point. If not, confirm integration depth and day-to-day operations for your stack.

Final Thoughts

Avanan (Check Point Harmony Email and Collaboration) is a cloud-first email security product with unified quarantine, DMARC monitoring, and user-reported phishing workflows.

GreatHorn

Best For

Teams that want layered, cloud-native email security with a strong emphasis on user engagement and human-layer defenses.

What It Is

GreatHorn is a cloud-native platform that combines phishing detection, user engagement, and incident response.

Key Capabilities

• Layered phishing protection and incident response
• Mailbox intelligence that gives users context to make better decisions

Considerations

For deep post-compromise containment such as ATO and sensitive data access constraints, validate how far it goes beyond user-facing context and standard remediation.

Final Thoughts

GreatHorn is a cloud-native email security platform that layers phishing detection with user engagement and incident response.

Sublime Security

Best For

Teams that want a detection-as-code email security platform with full control over rules and detection logic.

What It Is

Sublime is an email security platform built around customizable, transparent detection rules, with an open detection engine that teams can tune.

Key Capabilities

• Rules-based detections that are visible and editable
• A community of shared detection rules
• API-based deployment for Microsoft 365 and Google Workspace

Considerations

The control comes with operational work. Maintaining and tuning a rules engine takes ongoing analyst time, which lean teams should weigh against out-of-the-box detection. See Material vs. Sublime Security.

Final Thoughts

Sublime is a flexible, detection-as-code email security platform for teams that want hands-on control over detection logic and have the time to manage it.

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