Comprehensive Guide to Email Security Solutions

In late 2024, UK users received emails offering a free Starbucks “Coffee Lovers” box. Over 900 people reported it as a scam within two weeks. A similar email earlier that year delivered the ZeuS banking Trojan under the guise of a gift, silently stealing credentials.

These aren’t one-offs. 94% of organizations experienced email-based incidents last year, showing how easily everyday messages become security threats.

To stay ahead, more businesses now rely on dedicated email security solutions, tools that block phishing, malware, and impersonation attempts before they reach your inbox.

This guide breaks down why email security matters, what tools actually protect your team in 2025, and how to choose a solution that keeps you secure and productive.

What Are Email Security Solutions?

Email security solutions are tools that protect your inbox from threats like phishing, malware, spoofed senders, and data leaks. 

At their core, they’re designed to answer one question: Is this email safe to open, click, or trust?

The primary functions of these platforms usually include:

• Scanning emails for malicious links, attachments, or impersonation attempts

• Blocking known threats before they reach your inbox

• Encrypting sensitive messages so only the intended recipient can read them

• Authenticating senders using protocols like SPF, DKIM, and DMARC

• Monitoring unusual behavior, like a sudden invoice from a vendor you've never seen

Even if you're using something solid like Gmail or Outlook, that alone isn’t always enough to block clever scams. That’s why many businesses use extra tools that focus just on email security. These tools work alongside your existing setup. You don’t have to replace anything; they just connect with your current email and help you catch the bad stuff faster.

Example: Say, someone sends a convincing fake email that looks like it’s from your CFO. With built-in Microsoft spam filters, that message might slip through. But if you’ve integrated an email security solution,  it’ll check the sender reputation, scan the link, detect the impersonation pattern, and likely block or quarantine the message before it hits your finance team’s inbox.

Why Email Security Matters in 2025

Most businesses still rely on email to send contracts, invoices, passwords, and even payment details. And unfortunately, that’s exactly where attackers focus—because it works.

In the past, spotting a fake email was easy. You'd see bad spelling, weird email addresses, or awkward phrasing. But now? Scammers use AI to write emails that sound completely normal. They copy real employee names, use logos, and even time the messages around real events (like invoice dates or tax deadlines).

Let’s look at what’s actually happening right now:

• 1 in 4 emails is either malicious or unwanted spam, increasing the risk of accidental clicks or user fatigue. Source

• Business Email Compromise (BEC) losses reached $6.3 billion, making it one of the costliest cybercrime types globally. Source 

• Threat actors are now using generative AI to craft phishing emails and write malicious code, improving both scale and believability. Source

• 95% of data breaches involve human error. Source

In the new world, your email security is paramount. So below, we explore the types of email security solutions and list out the top providers to help you choose what fits your needs.

Types of Email Security Solutions

Not all email threats look the same, and neither do the tools that protect against them. Here are the most common types of email security solutions you’ll see today, and what each one is built to handle:

1. Secure Email Gateways (SEGs)

These act as a shield between your email server and the internet. They scan every incoming and outgoing message for spam, viruses, malware, and suspicious links before they ever reach your inbox.

Best for: Blocking mass phishing campaigns and known threats.

2. Email Encryption Tools

These ensure that only the intended recipient can read your message, even if it’s intercepted. Some tools encrypt everything by default; others let you choose when to secure sensitive info.

Best for: Legal, finance, healthcare, and anyone sharing confidential files or client data.

3. Anti-Phishing and Impersonation Protection

These tools go beyond spam detection. They look for patterns, language cues, and sender behavior to catch impersonation attempts like someone pretending to be your vendor or CEO.

Best for: Preventing Business Email Compromise (BEC) and fraud.

4. Authentication Protocols (SPF, DKIM, DMARC)

These are technical standards that verify whether an email is actually from who it claims to be. They help prevent spoofing and protect your domain’s reputation.

Best for: IT-managed domains and any business sending bulk or branded emails.

5. AI-Powered Threat Detection

These modern tools use machine learning to flag suspicious behavior that traditional filters might miss. For example, detecting an urgent tone in an invoice request that doesn’t match normal patterns.

Best for: Staying ahead of fast-evolving threats and deepfake-level scams.

Also Read: Top AI Email Management Tools for Inbox Cleanups in 2025

Up next: we’ll walk through the top-rated tools so you can compare features and find the right fit for your setup.

Top 5 Email Security Solutions for 2025

Choosing the right email security platform depends on what you're trying to protect and how your team works. The tools below offer strong protection against phishing, malware, spoofing, and data loss.

All five are well-established, widely used, and built to handle today’s threats, from QR code scams to AI-generated impersonation emails.

1. Mimecast

Mimecast is a cloud-based security platform focused primarily on email, with additional tools for archiving, continuity, and user training. It integrates tightly with Microsoft 365 and supports Google Workspace. Mimecast specializes in real-time protection against advanced threats and impersonation attacks, especially for businesses in regulated industries.

Key Features: 

• Comprehensive phishing protection: Uses AI-driven threat analysis to block malicious emails before they're opened.

• Advanced BEC defense: Detects CEO fraud, vendor impersonation, and payment scams using behavioral analysis.

• QR code defense: Scans and flags QR codes that lead to phishing websites.

• Advanced malware protection: Inspects attachments and links in real-time; quarantines threats with admin control.

• Integrated email intelligence: Aggregates insights from user reports to continuously improve detection.

2. Proofpoint

Proofpoint is a cloud-based email security solution tailored for small to mid-sized businesses. While focused on email, it also extends protection to internal communications and provides adaptive defenses based on threat intelligence from the Proofpoint Nexus platform.

Key Features:

• AI Threat Intelligence: Combines machine learning, behavioral analysis, and visual detection to block evolving threats.

• Click-Time Protection: Rewrites and scans URLs at the moment of click, using sandboxing and browser isolation.

• BEC & TOAD Defense: Detects zero-payload impersonation and callback phishing using AI-driven sender analysis.

• User Reporting Workflow: Real-time warning banners and a “report” button help users flag threats across devices.

• Internal Email Scanning: Monitors internal and external traffic to detect account takeovers and insider risks.

3. Barracuda Email Protection

Barracuda provides a robust, cloud-native platform that focuses on email security, backup, and compliance. It protects Microsoft 365 and Google Workspace users from phishing, malware, data leaks, and domain spoofing, while also offering continuity and archiving features.

Key Features:

• Spam & Malware Filtering: Blocks malicious messages and attachments using threat intelligence and heuristics.

• Impersonation & Domain Fraud Protection: Detects sender spoofing and impersonation using AI and DMARC validation.

• Data Loss Prevention & Encryption: Secures outbound messages and prevents leaks of sensitive information.

• Cloud Backup & Archiving: Provides automated email backup, archiving, and long-term retention policies.

• Incident Response & Awareness Training: Automates post-delivery threat remediation and provides phishing simulations for staff.

4. Microsoft Defender for Office 365

Microsoft Defender for Office 365 provides end-to-end protection against email threats, including phishing, malware, and business email compromise (BEC), across Microsoft Outlook, Teams, and collaboration tools. It supports both detection and response and is ideal for Microsoft 365 users seeking native integration and enterprise-grade protection across communication platforms.

Key Features:

• AI-powered sentiment analysis: Uses generative AI to analyze and filter malicious emails and messages.

• Inline user protection: Blocks harmful links and attachments directly within Outlook and Teams, with real-time warning banners.

• BEC attack disruption: Automatically isolates compromised users/devices and removes malicious content post-delivery.

• Security posture optimization: Applies recommended configurations to reduce risks across email and collaboration platforms.

• Priority account support: Offers heightened security measures for executive and high-risk accounts.

• Awareness and training: Provides phishing simulations and targeted training to boost employee cyber awareness.

5. Abnormal Security

Abnormal uses behavioral AI to stop advanced threats, including BEC, vendor compromises, and AI-crafted phishing, integrating instantly into Microsoft 365 or Google Workspace via API with no need to reroute mail or replace your existing gateway.

Key Features:

• Behavioral AI Detection: Learns normal communication patterns to spot subtle anomalies in email content and sender behavior.

• Automated Threat Response: Removes malicious emails and prevents employee interaction without manual intervention.

• Explainable Threat Insights: Provides detailed context, logs, and visual timelines for every blocked attack.

• Customizable Controls: Lets admins define risk thresholds and remediation actions, all from a unified console.

• Rapid Deployment & Adaptation: Connects in under a minute and keeps learning, tuning itself to new threats in real time.

Want to stay focused on the emails that matter, without compromising security? NewMail AI acts as your private, workspace-native assistant to surface important threads, auto-triage noise, and generate smart replies, all while keeping your data in your Google account. Explore NewMail AI Now.

Each tool excels at securing your emails, but selecting the right solution takes more than just comparing features. Before you decide which solution to deploy, it’s important to understand what actually makes an email security service effective for your organization.

How to Choose Email Security Solutions

With top providers like Mimecast, Proofpoint, Barracuda, Microsoft Defender, and Abnormal Security offering strong but different capabilities, your decision should reflect how your business operates, what threats you face, and how much control and visibility you need.

Here’s what to consider before committing:

1. Deployment Model (Cloud vs. On-Prem): Most modern tools are cloud-native, but some offer hybrid support if you have legacy infrastructure or strict data residency needs.

2. Scope of Protection: Some tools focus solely on email (like Abnormal and Proofpoint), while others (like Microsoft Defender and Mimecast) cover broader collaboration tools like Teams, SharePoint, or OneDrive.

3. Threat Detection Capabilities: Look beyond signature-based detection. Prioritize solutions that use behavioral analysis, AI/ML engines, and real-time threat intelligence to stop BEC, TOAD, and zero-day attacks.

4. User Experience and Reporting: Can end users report phishing with one click? Are warning banners contextual and mobile-friendly? Does your IT team get actionable forensics and dashboards?

5. Integration and Ecosystem Fit: Ensure the tool integrates cleanly with your email platform (e.g., Gmail or Microsoft 365), SIEMs, SOAR platforms, and existing security workflows.

6. Remediation and Automation: Tools with auto-quarantine, post-delivery link re-scanning, and auto-removal of malicious messages help reduce time-to-containment and limit manual workload.

Even with strong tools in place, human behavior and configuration choices still impact how well your defenses hold up.

Also Read: 6 Fundamentals of Email Inbox Organization

Best Practices for Email Security Management

These best practices help reinforce your technical setup with strong operational habits.

1. Enable Multi-Layered Protection

Don’t rely on a single line of defense. Use layered email security—combining spam filters, anti-phishing, malware scanning, and advanced threat detection like sandboxing or behavioral analysis. This ensures broader coverage across different attack types.

2. Enforce Role-Based Access and Least Privilege

Limit admin access and email rules to only what users need. Misconfigured permissions often lead to unauthorized email access or rule manipulation. Assign roles with care and audit them regularly.

3. Regularly Train Employees on Phishing Recognition

End users are often the last line of defense. Provide quarterly training and run simulated phishing exercises. Teach users to look for mismatched sender names, suspicious links, and urgent tone manipulation.

4. Monitor and Respond to Threats in Real-Time

Choose a solution with real-time alerting and automated remediation. Ensure your team can review user-reported emails quickly and remove threats post-delivery if needed. Periodically review logs to identify new patterns or evolving attacker behavior.

5. Integrate with Your Broader Security Stack

Your email security service should integrate with SIEM, EDR, and identity platforms. This enables faster correlation across systems and supports automated incident response across endpoints and users.

6. Audit Rules and Policies Quarterly

Over time, rule sets become outdated or overly complex. Conduct quarterly reviews of quarantine thresholds, allow/block lists, and forwarding rules to ensure your configuration reflects current risks and workflows.

Also Read: Best AI Email Assistant in 2025

Conclusion

Email remains the most targeted channel in the threat landscape, but it’s only one part of your broader security posture. As cybercriminals evolve their methods with AI-generated phishing, QR code exploits, and account compromise tactics, organizations must adopt layered defenses that protect communication, identity, and sensitive data at every level.

If your business relies heavily on email, NewMail AI can be your secure AI assistant to help manage and triage your inbox with confidence.

We built NewMail with security at its core. Your data stays within your own Google account, protected with military-grade encryption. We comply with GDPR and maintain Google Workspace security certification through regular third-party audits. 

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