Top 10 Best Secure Email Gateway Software of 2026

Proofpoint Email Protection is a top-tier Secure Email Gateway (SEG) solution that provides comprehensive defense against advanced email threats including phishing, malware, spam, and business email compromise (BEC). Leveraging AI, machine learning, and behavioral analysis, it offers real-time threat detection, URL and attachment sandboxing, and impersonation protection. Additionally, it includes data loss prevention (DLP), compliance reporting, and seamless integration with Microsoft 365 and other cloud environments for enterprise-scale deployment.

Mimecast Email Security is a cloud-native Secure Email Gateway (SEG) that delivers advanced protection against phishing, malware, ransomware, business email compromise (BEC), and impersonation attacks. It leverages AI, machine learning, and a global threat intelligence network for real-time URL scanning, attachment sandboxing, and precision threat detection. The platform also includes DMARC management, data loss prevention (DLP), and seamless integration with Microsoft 365 and Google Workspace for comprehensive email security.

Microsoft Defender for Office 365 is a cloud-native secure email gateway solution integrated into the Microsoft 365 ecosystem, providing advanced protection against phishing, malware, spam, and business email compromise. It uses AI-driven detection, Safe Links for URL rewriting and scanning, Safe Attachments for detonating files in a sandbox, and anti-impersonation tools to safeguard Exchange Online inboxes. The service also includes real-time threat intelligence from Microsoft’s vast network and automated response capabilities like Zero-hour Auto Purge (ZAP).

Cisco Secure Email Gateway is a comprehensive email security solution that defends against advanced threats like phishing, malware, ransomware, and business email compromise using AI-driven detection, sandboxing, and machine learning. It provides inbound and outbound filtering, data loss prevention (DLP), encryption, and impersonation protection, with support for both cloud-hosted and on-premises deployments. Integrated with Cisco's broader security portfolio, it leverages the Talos threat intelligence network for real-time updates and high-fidelity threat blocking.

Barracuda Email Security Gateway is a robust secure email gateway solution designed to protect organizations from spam, phishing, malware, ransomware, and advanced persistent threats using AI-driven detection and multi-layered defenses. It provides features like sandboxing for zero-day threats, data loss prevention (DLP), email encryption, and archiving, with flexible deployment options including cloud-hosted, on-premises appliances, and virtual machines. The platform integrates seamlessly with Microsoft 365 and other email systems, offering centralized management and reporting for IT teams.

Trend Micro Email Security is a cloud-based Secure Email Gateway (SEG) solution designed to protect organizations from email threats like phishing, malware, spam, and business email compromise (BEC). It employs AI-powered machine learning, sandbox analysis, and global threat intelligence to detect and block advanced attacks in real-time. The platform offers seamless integration with Microsoft 365, Google Workspace, and on-premises systems, along with customizable policies and detailed reporting for compliance and visibility.

Fortinet FortiMail is a robust secure email gateway (SEG) solution designed to protect organizations from email-based threats like spam, phishing, malware, and advanced persistent threats. It provides comprehensive filtering, antivirus scanning, data loss prevention (DLP), and encryption capabilities, with flexible deployment options including hardware appliances, virtual machines, and cloud-hosted services. Leveraging Fortinet's FortiGuard Labs for real-time threat intelligence, it integrates seamlessly with the broader Fortinet Security Fabric for unified management.

Symantec Email Security.cloud is a cloud-based secure email gateway (SEG) solution designed to protect organizations from advanced email threats such as phishing, malware, ransomware, and business email compromise (BEC). It leverages Symantec's global threat intelligence, AI-driven detection engines, and machine learning for real-time analysis of emails, attachments, and URLs. The platform also includes data loss prevention (DLP), sandboxing, and compliance reporting to ensure secure email communications.

Abnormal Security is an AI-native Secure Email Gateway (SEG) platform that uses behavioral AI and machine learning to detect and stop advanced email threats like phishing, business email compromise (BEC), ransomware, and account takeovers. Unlike traditional signature-based solutions, it analyzes user behavior, content, and relationships in real-time to identify anomalies without relying on rules or indicators of compromise. The cloud-native platform integrates seamlessly with Microsoft 365 and Google Workspace, offering autonomous protection and rapid response capabilities.

Sophos Email Security is a cloud-based secure email gateway (SEG) designed to protect organizations from spam, phishing, malware, ransomware, and business email compromise (BEC) attacks. It employs AI/ML-driven detection, dual antivirus engines, attachment sandboxing, and URL defense to analyze inbound, outbound, and internal emails in real-time. The solution integrates tightly with the Sophos security ecosystem for coordinated threat response and offers compliance features like data loss prevention (DLP).