What is email DLP? How it works and why you need it

Learn how email data loss prevention keeps sensitive information safe.

What is email DLP?

Email data loss prevention (DLP) is a security methodology for monitoring, detecting, and preventing the unauthorized transmission of sensitive information over email. It protects against cyber-attacks and accidental leaks due to human error – the leading cause of data breaches.

The 4 most common causes of email data loss

  1. Accidental exposure: selecting the wrong recipient, mistakenly sharing confidential files, etc.
  2. Phishing: clicking on malicious links or compromised attachments in phishing emails.
  3. Lack of encryption: sending sensitive information in unsecured emails that are vulnerable to interception.
  4. Insider threats: disgruntled employees who send sensitive data to competitors or leak confidential information deliberately.
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How does email DLP work?

To answer the question “What is email DLP?”, you have to understand how it works. Integrating seamlessly with your email client, email DLP solutions monitor your messages to prevent data breaches before, during, and after you hit send.

Before send

Email DLP solutions scan message content and attachments for sensitive data patterns, based on predefined rules. For example, credit card information, social security numbers, or healthcare data. They also check the recipient’s name and address and look for potential Bcc misuse.

Should it identify an issue, the email DLP solution:

  • Alerts

  • Encrypts

  • Blocks

  • Deletes

By acting immediately, email DLP solutions help to prevent both accidental and deliberate data leaks.

During send

Email DLP solutions encrypt messages to protect sensitive data during transit. Some solutions apply encryption automatically, while others let you choose which emails to encode.

Encryption works by converting standard email text (plaintext) into illegible code (ciphertext). Once the email reaches its destination, the recipient’s email client uses an encryption key, stored on their device, to unscramble the message.

The most secure email DLP solutions follow the zero-knowledge, zero-access methodology. Every email receives a unique decryption key stored on the recipient’s device. So, no one other than the intended recipient can access the message’s content – not even the email service provider.

After send

With Outlook and Gmail, you only have a short window to recall misdirected emails. That isn’t the case with email DLP. There are no time restrictions, meaning you can recall messages hours, or even days, after hitting send.

Additionally, advanced solutions let you revoke message access and set expiration dates on individual emails. This gives you complete control over when, where, and who can access them.

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Why do you need email DLP?

Despite the popularity of instant messaging apps like Microsoft Teams and Slack, email remains the channel of choice for most business comms. 74% of businesses say email remains the most effective channel for reaching employees.

However, standard email is inherently insecure. Popular email clients like Outlook and Gmail focus on getting messages from point A to point B. They only have basic security features and do little to protect sensitive data.

Email DLP solutions reduce your exposure to many of the risks associated with data breaches, such as:

  • Operational disruption

  • Reputational damage

  • Regulatory fines

  • Legal action

Data breaches

Unsecured emails are vulnerable to accidental exposure and malicious attacks. Without appropriate safeguards or robust security software, there’s nothing to stop employees from inadvertently sending sensitive information to unauthorized recipients or clicking on phishing links. A single lapse can result in a data breach, which can have disastrous consequences for your business – from losing customer trust to hefty fines.

Operational disruption

Data breaches can cause severe operational disruption. Post-breach investigation, remediation, and communication divert critical resources from normal business activities, impacting productivity. According to one survey, it takes seven months on average to fully recover from a cyber incident.

Regulatory fines

Whatever industry you work in, chances are you’re subject to some form of data protection regulation, such as GDPR. Non-compliance due to inadequate data security can result in fines and sanctions.

Reputational damage

A single data breach can tarnish the reputation you’ve worked so hard to build. This is particularly true if you operate in an industry that handles a lot of sensitive data, such as financial services or healthcare. People are understandably wary about working with companies that have suffered a breach. And while it is possible to regain your customer’s trust (depending on the nature of the breach), this takes time.

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5 business benefits of email DLP software

If you’ve ever asked yourself, “What is email DLP and why do I need it?”, there’s one crucial thing you must remember. Email data security isn’t just a people problem – it’s also a technology one.

Operating silently in the background, email DLP solutions ensure employees comply with security best practices while harnessing the power of AI to identify potential threats in real time.

1. Enhanced data security

Email DLP solutions protect sensitive information from unauthorized access. By monitoring email traffic, encrypting messages, and flagging issues, they secure your business data against breaches.

2. Cost savings

The initial investment in email DLP can be significant, but it’s a drop in the ocean compared to the financial consequences of a data breach. Efficient solutions also streamline data security operations, reducing the need for manual oversight and freeing up your employees to focus on more productive tasks.

3. Increased customer trust

Securing your main communications channel with an email DLP solution helps strengthen customer relationships. It’s simple: people find it easier to trust companies that go above and beyond to protect their data.

4. Regulatory compliance

Email DLP solutions supports compliance with various data protection regulations. Integrating it into your email client helps you avoid the financial penalties and sanctions associated with non-compliance.

5. Competitive advantage

As cybersecurity and data privacy awareness grows, robust email DLP becomes a key differentiator. Anything that strengthens your data protection capabilities makes it easier to attract new business, reassuring potential and existing customers that they’re in safe hands.

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Real-world email DLP examples

Hertsmere Borough Council

Hertsmere’s previous email security solution was expensive and difficult to use. With limited reporting capabilities, administrators struggled to monitor usage and compliance with data protection regulations. Realizing it was time for a change, they switched to Zivver Secure Email.

The user-friendly design has been a game-changer for Hertsmere. Integrating effortlessly with Outlook, 3x more staff use Zivver than the previous email security system – ensuring every email is secure.

When we explored alternative solutions, we saw that Zivver offered more functionality within the M365 environment, providing an overall easier experience for our teams. The ability to send files securely by email is key for our business, and Zivver’s large file sharing functionality is more integrated than our previous solution.”

Zahid Zarin, Information & Digital Services Manager Hertsmere Borough Council Read the case study

Soha Housing

Growing increasingly frustrated with its old email security system, Soha Housing decided to invest in a more intuitive solution. The team needed something that would let them share large files securely and in compliance with GDPR.

Zivver supports file transfers up to 5TB, and has a suite of security features, including advanced encryption and multi-factor authentication (MFA). This allows employees to send sensitive data quickly, safely, and confidently.

While compliance wasn’t the main reason for implementing Zivver, it is very important. We can access data and reporting on user activity in the back end, including some interesting statistics regarding data incidents avoided. We can even see when emails have been recalled. This data supports us in meeting [GDPR] compliance.”

James Ryan, Infrastructure Manager Soha Housing Read the case study

Royal Papworth Hospital

For the UK’s leading heart and lung hospital, enabling patients to communicate easily with staff while protecting confidential health data is essential.

Zivver Conversation Starter lets internal stakeholders and patients send emails and large files securely without needing to create an account. Additionally, MFA enables patients to choose their preferred authentication method for fast, accessible, and accurate verification.

One of the main things that attracted me to Zivver was the fact that it enables two-way secure email. This means that not only can our employees email securely, but non-Zivver users outside of the trust, including patients, can email our staff securely, too. Zivver makes this really easy. Recipients don't need to create Zivver accounts or login to any portals. It’s as easy as replying to an email!”

Cath Willcox, Head of Information Governance & Health Records Royal Papworth Hospital Read the case study

Why Zivver

The average cost of a data breach rose to $4.88 million in 2024 – almost $500,000 more than in 2023. When the stakes are this high, organizations that handle sensitive information need more than basic email security. They need advanced, intelligent solutions that can adapt to evolving threats.

Zivver Secure Email helps organizations in every industry improve data security and compliance with its robust toolset, featuring:

Intelligent filtering and detection

Advanced algorithms analyze email content for sensitive information. Unlike traditional systems, which rely on predefined rules, Zivver's DLP solution uses machine learning to improve detection accuracy and reduce false positives.

Real-time prevention and remediation

When Zivver detects a potential issue, it doesn’t just alert the user – it provides real-time recommendations on how best to fix it. For example, if an employee mistakenly addresses an email containing sensitive client data to the wrong recipient, Zivver prompts the user to correct the error before hitting send. Not only does this help prevent data breaches, but it also educates users and reinforces email security best practices.

Compliance assurance

Enforcing data security compliance across a large organization is easier said than done. Zivver simplifies the process, with built-in safeguards that reduce human error and advanced security features – like encryption. It’s also compatible with all major data protection regulations, including:

Seamless integration

Zivver integrates seamlessly with leading email clients, such as Outlook and Gmail, providing an effortless experience for sender and receiver. DLP Gateway encrypts all outgoing emails, with no need for manual intervention. So, unlike other email DLP solutions, you can send secure emails in a few simple clicks – you don’t even need an account.

Detailed reporting and analytics

Understanding the flow of sensitive information inside and outside your organization is central to effective data security. Zivver’s reporting tools give IT departments and compliance officers insight into email traffic patterns, security threats, compliance status, and more. This helps you create accurate, detailed security assessments and audits.

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