Email encryption services, by compliance need and encryption depth

What to look for, and what to ignore

What Email Encryption Service actually costs

Email encryption pricing splits into two distinct markets. Consumer and small-business encrypted email providers (Proton Mail, Tuta) charge $3–$13 per user per month for encrypted mailboxes with calendar and storage. Enterprise encryption gateways and add-ons (Virtru, Zix/OpenText, Microsoft Purview) charge $2–$8 per user per month as an overlay on existing email infrastructure. The total cost depends heavily on whether you are replacing your email provider or adding encryption to an existing one.

For a mid-market organization with 200 users on Microsoft 365, the most cost-effective path is enabling Microsoft 365 Message Encryption (already included in E3/E5) and adding Virtru or a similar gateway ($5/user/month, ~$12,000/year) for policy-based encryption that covers external recipients. For a small firm or privacy-focused organization that wants a dedicated encrypted provider, Proton Mail Business at $6.99/user/month (~$16,800/year for 200 users) replaces the email provider entirely. The S/MIME route is cheapest on paper ($12–$30/user/year for certificates) but most expensive in operational effort.

How to compare them

Encryption method and key management

The encryption method determines what you are protected against. TLS protects transit only. S/MIME and PGP protect message contents end-to-end but require certificate management. Proprietary E2EE simplifies key management but locks you into a vendor's ecosystem.

Ask: What encryption standard does the service use? Who holds the encryption keys? Can the organization recover encrypted messages if a user loses access? Can you export keys if you switch providers?

Integration depth with existing email platform

The tighter the integration, the higher the adoption rate. A solution that requires users to switch email clients or use a separate portal will have low compliance.

Ask: Does the service integrate natively with Microsoft 365 or Google Workspace? Does it work within Outlook, Gmail, and mobile mail clients without requiring a separate app? Is there an API for programmatic encryption?

Policy-based automatic encryption capabilities

Automatic encryption based on content patterns, recipient domains, or data classification labels removes the dependency on user behavior and ensures consistent coverage of regulated content.

Ask: Can the service automatically encrypt messages based on content keywords, regular expressions, or DLP classifications? Can policies be applied at the domain, group, or individual level? How are policy exceptions handled?

External recipient experience

Your encryption is only as good as recipients' willingness to engage with it. If the recipient experience is cumbersome, users will circumvent encryption to avoid complaints.

Ask: What does a non-subscriber see when they receive an encrypted message? Do they need to create an account? Can they reply encrypted without installing anything? Test this with actual external contacts during evaluation.

Compliance reporting and audit trail

For regulated industries, the ability to prove that encryption was applied is as important as the encryption itself. Without audit logs, you cannot demonstrate compliance during an examination.

Ask: Does the service log all encryption events with timestamps, sender/recipient, and encryption method? Can reports be generated for specific compliance frameworks? Are logs exportable to SIEM platforms?

Data portability and vendor lock-in risk

Switching encrypted email providers is harder than switching regular email providers because encrypted message archives may not be portable. Understanding the exit path before you enter is critical.

Ask: Can encrypted messages be exported in a standard format (MBOX, PST) with decryption keys? If you leave the service, can you still access historically encrypted messages? What is the data retention and deletion policy?

Before you buy

1. 1Define your threat model: Are you protecting against interception in transit, server-side access by the provider, or both? This determines whether TLS, gateway encryption, or end-to-end encryption is appropriate.
2. 2Map your regulatory requirements: Identify every compliance framework that applies to your email communications and document the specific encryption requirements for each.
3. 3Inventory your email infrastructure: Document your current email platform (Microsoft 365, Google Workspace, on-premises Exchange), client applications (Outlook, Gmail, mobile), and existing security tools (DLP, email security gateway).
4. 4Assess your external communication patterns: What percentage of sensitive email goes to external recipients? How technically sophisticated are those recipients? This determines how important the external recipient experience is.
5. 5Evaluate integration depth with your existing email platform: Test that encryption works seamlessly in Outlook, Gmail, and mobile clients without requiring users to switch applications or change workflows.
6. 6Test the external recipient experience: Send encrypted messages to contacts on Gmail, Outlook.com, Yahoo, and corporate Exchange during your POC. Collect feedback on the receiving experience.
7. 7Verify key management and recovery capabilities: Confirm that the organization can recover encrypted messages when employees leave, and that key escrow works for compliance and eDiscovery requirements.
8. 8Check archiving and eDiscovery compatibility: Ensure encrypted messages can be searched, archived, and produced during legal discovery without decrypting the entire archive.
9. 9Evaluate policy-based encryption capabilities: Test content-based, recipient-based, and domain-based automatic encryption rules against your specific sensitive data patterns.
10. 10Negotiate data portability terms: Understand what happens to encrypted messages if you leave the service. Can you export and decrypt your archive? Is there a read-only access period after cancellation?