The Best Secure Email Services To Protect Your Business Data

Email, as one of the most widely used methods of communication, requires robust measures to safeguard sensitive data and ensure privacy. Without adequate protection, every email exchange is a potential target for data breaches and cyber threats.

Fortunately, there is a range of secure email services available that offer your business advanced security features.

To compile this list, we have thoroughly evaluated the most popular secure email providers on the market based on their encryption methods, authentication processes, and other core considerations, such as pricing and usability.

What Is A Secure Email Service?

A secure email service introduces robust security measures into email communications, going beyond standard encryption. It includes enhanced features designed to prevent email-borne threats.

Such services often feature strong encryption protocols and identity authentication to protect against interception and errors.

Additional elements like email recall, security triggers, and comprehensive audit trails support compliance with industry regulations.

Why Do You Need A Secure Email Service?

Everyday business is steadily migrating online, with organisations relying heavily on email and other digital services to complete everyday tasks.

Originally designed as a simple file-sharing system, email has evolved into a critical tool for business communications, though it lacks built-in protections against many modern digital threats.

32% of UK businesses are reported to have experienced an attack or breach between 2022 and 2023, with 31% estimating they were attacked at least once a week.

This is largely thanks to a high level of phishing attacks, with 83% of businesses stating that this is one of the most common malicious threats they experience.

However, organisations are also at risk of human errors, such as misdirected emails. Research has determined that 88% of all data breaches are caused by an employee's mistake.

Types Of Secure Email Service

Depending on the threats you wish to protect against, there are a variety of secure email services available to utilise.

Most secure email software focuses on providing protection from either inbound or outbound threats, so businesses should determine which type of solution they are looking for. To summarise:

• Outbound email security secures messages and attachments leaving your infrastructure, reducing the chance of a data breach that results from sensitive data being accessed by the wrong person.
• Inbound email security software deals with incoming emails, scanning them for malicious content and ensuring they remain encrypted until the intended recipient gains access.

Depending on the size of your organisation, there will be different email security options to choose from.

For example, for enterprises and large businesses, a secure email gateway (deployed at server level) can offer comprehensive protection for all your employees who are communicating with your customers.

For smaller companies, desktop-based solutions are a cost-effective alternative that can be installed and utilised on an individual basis.

Choosing A Secure Email Service

There are several recommended features you should be looking for when choosing a secure email service. These include:

• strong encryption, with AES-256 generally considered to be one of the most secure algorithms available today;
• recipient authentication, which enables senders to verify that the person accessing secure messages is exactly who they say they are;
• email recall, allowing users to revoke access to secure emails sent in error;
• audit trails, helping you to adhere to regulations and maintain compliance within your organisation.

Best Secure Email Services

Whether it's Microsoft's Outlook encryption, Egress's machine learning, Zivver's focus on human error, or Mailock's user-centric approach, there is a solution designed to fit your business's specific needs.

Mailock Secure Email

Mailock is described as a dedicated outbound email solution, enhancing the secure delivery of confidential information using your existing email setup.

It's highlighted for its suitability across a wide range of businesses and availability in two formats: as a desktop service or an enterprise-level secure email gateway.

Mailock offers users:

• end-to-end AES-256 encryption, with recipients granted unlimited secure replies;
• recipient authentication, with a choice between SMS, Q&A, Unipass ID, and email verification;
• full email revoke for any message or attachment sent securely, available at user level;
• Read notifications, informing senders when their secure email has been opened;
• audit trails, allowing users to track the open status of their messages, attachment opens, and recall statuses;
• trigger words - a list of pre-determined phrases that, when spotted within the body or subject of an outbound email, prompt the user to send their message securely.

Key considerations:

Recipients can read Mailock messages without creating an account. If they wish to reply, they can sign up for a free account, which includes a limited number of secure sends a month. Mailock also offers an Outlook Add-in for integration with Microsoft Outlook.

Learn more about Mailock.

Microsoft Purview Message Encryption (MPME)

Microsoft Purview Message Encryption (MPME), previously known as Office Message Encryption (OME), is Microsoft’s updated secure email service and is included in enterprise 365 packages (such as E5).

Microsoft Purview Message Encryption (MPME) offers users:

• military-grade AES-256 encryption, with encrypted replies available for recipients;
• message recall, available only under certain conditions to senders or to administrators who are familiar with PowerShell;
• recipient inbox access verification, including one-time code, Microsoft sign-in, and Google sign-in;
• read receipts, which can be requested by the sender upon email composition and either accepted or denied by the recipient when opening a message;
• a compliance dashboard with a full audit trail, providing details on sent secure messages including timestamps and recall statuses.

Key considerations:

Read our complete review of Microsoft's MPME email encryption.

Egress Cloud Email Security Suite

Egress offers customers secure email as part of their Intelligent Cloud Email Security Suite including Egress Defend, Prevent, and Protect.

The combined products are designed to protect against inbound and outbound email threats by reducing human error and risk.

The Egress Intelligent Cloud Security Suite offers users:

• end-to-end AES-256 encryption, which can be applied by individual users or administrators;
• configurable access privileges, such as restrictions on forwarding, printing, and downloading;
• recipient authentication, with users able to set Q&A challenges to recipients which must be passed to gain access;
• machine learning program that analyses outbound email contents for potential threats and prompts users to send securely;
• integrations with Microsoft 365 and a dedicated Outlook add-in.

Key considerations:

Encrypted replies are available when the recipient has created a free account. Free users have 25 credits per month, with 1 credit equating to 1 recipient.

Read our comparison guide to Egress' secure email capabilities.

Zivver Secure Email

Zivver is a secure email service designed to protect against outbound email threats, mainly focusing on the risks associated with human error.

Their product set delivers machine learning and large file transfer capabilities to prevent the accidental sending of sensitive data to the wrong recipients, thus enhancing overall email security and mitigating potential data breach incidents.

Zivver offers users:

• RSA 2048 level encryption to secure messages and attachments;
• recipient authentication, including access code, SMS, and email verification;
• secure file transfer, facilitating large file sizes up to 5TB;
• email recall and expiration periods, available when the Zivver Outlook add-in is used;
• contextual correction, powered by machine-learning capabilities to scan outbound emails for potential errors and recommend secure sending.

Key considerations:

Zivver offers both an Outlook add-in and a Chrome extension. Certain features are only available for particular licence types.

Read our Zivver vs Mailock breakdown to learn more.

Mimecast Secure Email Messaging

Mimecast specialises in email security and continuity solutions for enterprise-level organisations.

Mimecast offers a suite of services designed to protect organisations against phishing attacks, malware infections, data leaks, and email system disruptions, utilising technologies such as machine learning and real-time scanning.

Mimecast Secure Email Messaging offers users:

• AES-256 email encryption that can be initiated manually or automatically based on specific criteria such as recipient domain or presence of certain keywords;
• options for email recall, including a manual recall by senders and a preset expiration of messages that establishes when they become unavailable for the recipient to access;
• two-factor authentication for account security, though it lacks recipient-specific authentication for individual messages;
• read receipt notifications, allowing senders to confirm when recipients open messages;
• customisable branding for outbound secure emails, allowing incorporation of company logos, colours, and names managed within Mimecast’s administration console.

Key considerations:

The user interface can be complex and requires training, as noted in user reviews. This may present a challenge for organisations without the capacity to invest in extensive training.

Customer support has been described as challenging, with some users finding it unresponsive. This could be a critical factor for businesses that require frequent and reliable support.

Pricing is tailored for larger organisations, with most plans starting from 100 seats, potentially making it less accessible for smaller businesses.

Read our Mimecast vs Mailock comparison to learn more.

Proofpoint Email Encryption

Proofpoint offers extensive email security and encryption services to protect sensitive information sent through email.

Their email encryption solution is included in a wider range of security products designed to secure sensitive data across multiple channels.

Proofpoint Email Encryption offers users:

• AES-256 email encryption that operates on an organisation's pre-established policies, allowing administrators to set rules for automatic email encryption based on the content or context of the message;
• message revoke, controlled by account administrators that enables them to block a recipient's access to a message;
• integrations with popular email platforms like Outlook and Gmail, enhancing its usability within existing workflows.

Key considerations:

Proofpoint requires an initial setup and configuration by IT professionals to integrate it properly with existing email systems. Additionally, recipients are required to create a Proofpoint account to access any secure emails.

The solution also offers no form of recipient authentication, and messages are only stored within the system for 15 days, potentially making them unsuitable for auditing purposes.

Read our Proofpoint vs Mailock article to learn more.

The Best Secure Email?

As digital communications continue to dominate business practices, employing the best secure email service is a non-negotiable necessity.

With the range of services available, choosing the most fitting solution can seem daunting. However, with Mailock's robust security features, seamless user experience, and flexible packages, it stands out as a leading choice for businesses of all sizes.

Want to learn more about how Mailock can help protect your business data? Try Mailock for a secure, seamless email experience that prioritises the safety of your business communications.

Reviewed By:

Sam Kendall, 07.06.24

Sabrina McClune, 07.06.24