Mimecast vs. Mailock: Secure Email Solutions Compared

Protecting sensitive data in email communications is crucial. Email is particularly vulnerable to cyber threats, prompting organisations to adopt security solutions to safeguard customer data effectively.

We’ll look at how two popular secure email services compare: Mimecast’s email security suite and Mailock.

We’ll explore how they support outbound email security across:

• Outbound Email Protection: Encryption strength, authentication types, and recall options.
• User Experience and Integrations: How easily they embed into your existing workflows.
• Customer Service and Cost: Levels of support and pricing flexibility for different teams.

Mimecast vs Mailock: At A Glance

Encryption

• Mimecast: AES-256 encryption, applied automatically or manually using policies.
• Mailock: AES-256 end-to-end encryption, with enhanced key management to protect data in transit.

Recipient Verification

• Mimecast: No recipient-specific verification, just a shared password model.
• Mailock: Multiple methods - SMS code, Q&A challenge, Unipass ID, and email verification.

Message Recall

• Mimecast: Manual recall if the message is unopened, or automatic expiry after 30 days.
• Mailock: Recall even after the recipient has opened the message.

Free Read-and-Reply

• Mimecast: Requires login to read and reply.
• Mailock: Recipients can read without registration. Replies require a free account.

Read Receipts and Audit Trail

• Mimecast: Read receipts available, full audit trails not included in core messaging service.
• Mailock: Full audit trail with automatic read notifications and attachment tracking.

What Is Mimecast?

Mimecast is a cybersecurity provider focused on protecting businesses from email-based threats such as phishing, malware, and data loss.

Its secure messaging service helps organisations protect sensitive data and ensure regulatory compliance by encrypting outbound messages and monitoring access.

Headquartered in London, Mimecast serves a global customer base with email security, continuity, and archiving solutions.

Mimecast: Outbound Security Features

Encryption

Mimecast uses AES-256 encryption and allows administrators to apply it based on content or recipient rules.

Messages expire after 30 days by default. Businesses needing long-term access logs may need additional tools.

Message Recall

Senders can manually recall unopened messages or rely on preset expiration. Messages cannot be recalled once opened.

Recipient Verification

Mimecast does not include recipient-level verification. Secure messages are accessed using a shared password, which can introduce security risks.

Read Receipts and Auditing

Read receipts are available on request. Full auditing is not included in the core secure messaging product.

Branding

Admins can apply corporate branding, including logos, colours, and company names. These are managed through a central console and can be toggled by message type.

User Experience and Integrations

Mimecast integrates with Outlook, its own portal, and a mobile app. Users can initiate encryption via trigger words or set rules.

Recipients do not need to download software but must log in to access messages.

Mimecast holds a customer rating of 4.3 on Capterra, with positive feedback for ease of use.

Customer Support and Pricing

Mimecast offers support through knowledge articles, video guides, and community forums. Direct assistance is available depending on your plan.

Licences typically suit organisations with 100+ users. Plans start at £3.75 per user per month, with custom pricing for larger deployments.

Free trials and demos are available on request.

What Is Mailock?

Mailock, developed by Beyond Encryption, is a secure email solution that protects sensitive information through encryption and recipient verification.

It enables organisations to reduce print and postal costs, meet regulatory requirements, and prevent data loss when sending confidential messages by email.

Mailock is widely used across financial services, legal, and accounting sectors to secure communications and demonstrate compliance.

Mailock: Outbound Security Features

Encryption

Mailock applies end-to-end AES-256 encryption, securing both message content and attachments.

Security policies can be set by admins or triggered by users via keywords. Key management ensures only intended recipients can decrypt a message.

Recipient Verification

Mailock offers layered authentication, ensuring messages are only accessed by verified recipients:

• SMS: Sends a one-time code to the recipient’s phone.
• Q&A Challenge: Customisable question only the recipient can answer.
• Unipass ID: Digital certificate verification used in financial services.
• Email verification: For low-risk messages where identity is already confirmed.

Message Recall

Messages can be recalled at any time - even if already opened - via the Mailock Outlook add-in or web interface.

Read Receipts and Audit Trail

Read notifications and a complete audit trail are included by default, showing who opened what and when, with full visibility on attachments.

User Experience and Integrations

Mailock is designed for ease of use. Recipients can read secure messages without needing to create an account. To reply, they simply register for a free account with 5 secure sends per month.

The platform integrates with Microsoft 365 via an Outlook add-in and supports secure web access.

Customer Support and Pricing

Mailock offers personal support during setup and everyday use, rated 4.7 on Capterra. A demo and free 14-day trial are available.

There are three licence options:

• Free: 5 sends per month, read receipts, Q&A authentication, Outlook add-in.
• Pro: From £9.30/user/month. Adds SMS, Unipass, branding, audit trail, and recall.
• Enterprise: Custom pricing for volume usage. Includes API, analytics, bulk sending, and hosting options.

Licences are billed monthly with no minimum seat requirement.

Mimecast vs Mailock: Which Is Right for You?

The best secure email solution depends on your organisation’s size, needs, and regulatory obligations.

Mimecast is well-suited to larger firms looking for inbound threat protection and brand control but lacks recipient-level verification and flexible licensing.

Mailock stands out for outbound email protection. With powerful recall, authentication options, and recipient-friendly UX, it’s trusted across finance, legal, and other regulated sectors.

The good news? You don’t need to choose between them.

Mimecast integrates with Mailock, enabling a layered approach to secure communication.

⬇️ Download the fact sheet

References

Mimecast Email Security Reviews, Capterra, 2024

Mailock Reviews, Capterra, 2024

Mimecast-Mailock Integration Guide, Mimecast, 2024

Reviewed by

Sam Kendall, 12.06.24

Sabrina McClune, 19.06.25