10 Email Security Best Practices to Follow

The Need for Email Security

To stay protected, organizations must follow proven email security best practices that minimize the risk posed by these threats. Malicious actors often target confidential information and employ credential theft techniques to gain unauthorized access and conduct further attacks. Below are 10 email security best practices to help strengthen your protection strategy. But first, let’s dive into why email security is so important in the current threat landscape. Phishing emails may no longer contain obvious grammatical errors, as attackers leverage generative AI to craft convincing messages, making them harder to detect.

Why Email is the Most Popular Attack Vector

Cybercriminals favor email as an attack vector for several key reasons:

• Primary Channel for Business Communication: Almost every employee uses email daily, creating a broad, consistent attack surface.
• Delivery of Malicious Content: Attackers can distribute phishing links, infected attachments, or fraudulent requests through legitimate-looking messages that actively deceive recipients.
• Enables Social Engineering Attacks: It’s easier to trick a human than to hack software systems. Email messages can be manipulated through a variety of social engineering techniques, including impersonation, urgency, and trust-based deception. Attackers often impersonate well known brands to increase the credibility of their phishing attempts.
• Tight Integration with Other Business Systems: Email systems connect to collaboration platforms, calendars, document management tools, and other systems, allowing cybercriminals to broaden the scope of their attacks.
• Storage of Sensitive Data: Many organizations use email to send or store confidential files, client information, and financial data, and other confidential information. This makes it a valuable target for data theft.

10 Best Practices To Strengthen Your Email Security

#1. Increase Sender Trust with Secure Email Authentication Protocols

Implementing secure email authentication protocols like SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting & Conformance) is a critical email protection best practice. These protocols authenticate senders, limiting email spoofing and domain impersonation, crucial tactics used in phishing and Business Email Compromise (BEC) attacks. Domain owners can use DMARC policies to specify how unauthenticated emails should be handled, helping to protect their domains from spoofing and phishing attempts.

Secure email authentication protocols form the foundation of enterprise email security, blocking messages from impersonated senders and limiting the social engineering playbook available to attackers. However, while they offer valuable protection against attackers impersonating trusted parties, secure email authentication does not block all phishing attacks.

#2. Strengthen Access Control with Robust Password Management

Effective password management is an often-overlooked but essential component of email security. Weak or reused passwords are a leading cause of account takeovers and data breaches. Weak passwords expose your organization to brute-force attacks. Employees reusing passwords across multiple systems means your email security is only as strong as their weakest account. Compromised credentials from one of their personal accounts could end up impacting your email infrastructure.

Email usage policies should require users to have complex, unique passwords. While complex passwords—using a mix of symbols, numbers, and letters—were once the standard, current best practices recommend strong passwords that are long, unpredictable, and easy to remember, such as passphrases. Strong passwords are now defined more by their length and unpredictability than by complexity alone. This process can be simplified by deploying password managers that automatically generate and store credentials.

#3. Add an Extra Layer of Defense with Multi-Factor Authentication (MFA)

A related email security best practice is Multi-Factor Authentication (MFA). MFA limits the impact of compromised credentials by adding an extra layer of protection beyond passwords. MFA requires users to verify their identity through two or more factors. So rather than just entering a password (which can be easily compromised in phishing attacks), they must provide a secondary method to verify their identity. This could be a one-time code sent to a trusted device or biometrics such as face recognition, or a one time password (OTP) generated by an authentication app.

Mandating MFA across your organization significantly strengthens the security of email accounts and limits the risk of account takeovers. Users deceived into providing their login credentials can maintain the security of their accounts by blocking malicious access attempts.

Combined with secure email authentication protocols and strong password policies, MFA enhances overall authentication and access control. Ensuring all parties involved are who they say they are to protect sensitive corporate communications and intellectual property, and to prevent customer data from being exposed or misused.

#4. Use Strong Email Encryption

Email encryption ensures that only authorized users can read the contents of your emails, protecting sensitive business and customer data from eavesdropping and man-in-the-middle attacks. This is especially critical for sectors that handle regulated data, such as healthcare, finance, or legal services. As part of a comprehensive security strategy, implementing email encryption not only safeguards data integrity but also helps maintain compliance and build customer trust.

#5. Create a First Line of Defense with a Secure Email Gateway (SEG)

Secure Email Gateways (SEGs) scan inbound and outbound messages for spam, malware, phishing attempts, and malicious attachments, including scanning all email attachments for potential threats. Beyond email threat monitoring, SEGs as part of network security solutions also help enforce data loss prevention (DLP) policies by ensuring sensitive information is shared only with trusted parties and that proper email encryption is in place. It is important to never open attachments from unknown or untrusted sources, as these may contain malware or phishing content.

When properly configured, SEGs reduce your attack surface and improve overall enterprise email security. However, employees should remain cautious even with attachments from trusted sources, as these can be compromised and used to deliver threats. SEGs should be considered the first line of defense and deployed alongside advanced email filtering tools designed to catch more sophisticated threats. Using the spam button in your email client can also help filter out suspicious emails and reduce exposure to potential threats.

#6. Implement Advanced Email Threat Monitoring Techniques

The best email security companies now offer advanced, AI-driven technologies that improve threat detection and response capabilities. With AI email threat monitoring, you can catch the most convincing phishing messages as well as sophisticated zero-day exploits. These solutions help prevent threats from ever reaching the user’s inbox, reducing the risk of compromise. Technologies to look for in email security tools include:

• Anomaly detection that identifies suspicious behavior and emerging email threats.
• Machine learning analytics that adapt filtering policies to improve detection accuracy and respond to new techniques.
• Natural Language Processing (NLP) models capable of analyzing messaging to spot sophisticated impersonation attempts.

Combining these advanced email filtering tools with enhanced threat intelligence feeds, you have the best technologies working with the most up-to-date and complete datasets. This approach significantly improves both threat detection coverage (catching more threats) and accuracy (catching threats without blocking legitimate emails) compared to traditional strategies focused on signature-based monitoring and fixed rulesets. Advanced monitoring can also help detect credential theft attempts before attackers can compromise accounts and use stolen credentials for further malicious activities.

#7. Reduce the Impact of Attacks with Automated Incident Response

Combining email threat monitoring with automated incident response capabilities is one of the most powerful email security best practices for reducing risk and ensuring business continuity. Automated incident response helps reduce risk across the organization by swiftly containing threats and minimizing the window of exposure. Advanced email threat monitoring solutions must detect anomalies in real time, implement automated security controls in response, and integrate with broader security tools to deliver holistic protection.

By responding quickly and using a range of security controls, from blocking emails to quarantining or sandboxing suspicious messages, you can minimize the impact of potential threats. This reduces downtime and the level of access gained by compromised accounts to prevent significant data breaches. Implementing feedback loops that inform users about the outcomes of their reports is essential for reinforcing security behaviors and continuously improving incident response effectiveness over time.

#8. Consider Mobile and Remote Email Security

With employees increasingly accessing work emails from smartphones and other remote devices, mobile email security is now a critical aspect of any robust strategy. Mobile email security best practices should focus on MDM (Mobile Device Management) and ensuring that any device connecting to your email servers has sufficient protection in place. Accessing email over public wi or public wi fi networks introduces significant risks, as these open networks are vulnerable to hacking and data interception. Malicious actors can exploit unsecured public networks to intercept sensitive information, including email credentials and confidential communications. This includes enforcing device encryption, implementing automatic lockouts, and enabling remote wiping for lost or stolen devices.

#9. Develop Engaging User Awareness and Training Programs

Human error is typically the weakest link in email security. Regular employee phishing training and awareness programs, user training initiatives that focus on human centric security approaches, help users recognize suspicious emails based on the latest social engineering tactics. Many employee phishing training modules now use more engaging strategies to improve the user experience and increase knowledge retention. This includes interactive training modules and simulated phishing campaigns to teach employees what to look for in potential phishing emails and how to respond to different types of threats. Ongoing efforts to train employees are essential to ensure they can recognize and respond to evolving threats effectively.

#10. Define Clear Email Usage Policies That Ensure Compliance

Another vital aspect of reducing human email security risk is governing how employees use emails. Strong email usage policies define how employees should handle, share, and store company information via email. These policies determine acceptable use and place restrictions on the sharing of sensitive information.

Email usage policies should be informed by privacy and data protection laws to ensure compliance across your organization. With well-defined and clear email usage policies, you can reduce insider risks while demonstrating a commitment to email protection best practices and regulatory integrity.