DigiCert Secure Email (S/MIME) Certs vs Beyond Encryption Mailock for M365: 2026 Comparison

DigiCert Secure Email (S/MIME) Certs

Organizations that need legally defensible email encryption without rebuilding their mail infrastructure should start with DigiCert Secure Email (S/MIME) Certs. S/MIME works natively in Outlook, Gmail, and Apple Mail, meaning adoption friction stays low and you avoid the gateway appliance tax. The tool maps directly to NIST PR.AA (authentication via public/private key pairs) and PR.DS (message-level confidentiality and integrity), covering the core email security control most compliance auditors actually care about. Skip this if your threat model demands perfect forward secrecy or sender anonymity; S/MIME signs identities, not conceals them.

Beyond Encryption Mailock for M365

SMB and mid-market teams standardized on Microsoft 365 should pick Beyond Encryption Mailock for M365 if message revocation is non-negotiable; the ability to recall emails even after a recipient opens them covers the mistake you'll inevitably make sending sensitive data to the wrong person. AES-256 encryption with SMS and Q&A recipient verification handles NIST PR.AA without requiring users to manage separate identity infrastructure. Skip this if your organization needs DLP that catches data before it leaves the network or if you're already enforcing encryption at the gateway level; Mailock layers on top of M365 rather than replacing email security controls.