Email Security, S/MIME Certificates
Sign and encrypt every email. Prove it came from you.
S/MIME certificates let you digitally sign outgoing emails, giving recipients cryptographic proof that every message is genuinely from you and hasn’t been tampered with in transit, and encrypt content so only the intended recipient can read it. Four validation levels cover every use case, from personal privacy to executive-level trust.
S/MIME Certificates at a glance
Basic S/MIME
For personal privacy
Digitally sign and encrypt email for a single address. No identifying information beyond your email address. Ideal for personal communications requiring privacy and integrity.
? Email address validation
? Digital signing
? Email encryption
? No additional info required
IV S/MIME
For verified professionals
Validates your first and last name in the digital signature. Builds professional credibility for client-facing communications. Ideal for lawyers, accountants, engineers, doctors, and notaries.
? Individual name validation
? Digital signing
? Email encryption
? Verified professional identity
OV S/MIME
For organizations
Validates your organization’s name. Prevents CEO identity fraud and corporate impersonation. Ideal for functional addresses: support@, billing@, admin@.
? Organization name validation
? Digital signing
? Email encryption
? Anti-fraud for org addresses
Sponsor S/MIME (IV + OV)
For executives & key personnel
Validates both individual and organizational identity. Maximum trust for executive communications. The strongest defense against sophisticated impersonation attacks.
✓ Individual + organization validation
✓ Digital signing
✓ Email encryption
✓ Prevents internal & external tampering
How S/MIME certificates stop email spoofing and BEC attacks
Email was not designed with authentication in mind. Without S/MIME, there is no cryptographic way for a recipient to know that an email actually came from the person or organization it claims to be from, hasn’t been modified since it was sent, or contains content that only the intended recipient can read.
S/MIME solves all three. It adds a tamper-evident digital signature to every outgoing message and optionally encrypts the content: all using a certificate issued and validated by SSL.com, a trusted, WebTrust-audited Certificate Authority.
Compare S/MIME Certificates
| Feature | Basic S/MIME | IV S/MIME | OV S/MIME | Sponsor S/MIME |
|---|---|---|---|---|
| What is validated | Email address only | Individual’s name | Organization name | Individual + organization |
| Best for | Personal email privacy | Professionals | Organizations: functional addresses | Executives, key personnel |
| Digital signing | ✓ | ✓ | ✓ | ✓ |
| Email encryption | ✓ | ✓ | ✓ | ✓ |
| Individual name in signature | ✗ | ✓ | ✗ | ✓ |
| Organization name in signature | ✗ | ✗ | ✓ | ✓ |
| Prevents CEO/executive impersonation | ✗ No | ⚠ Partial | ⚠ Partial | ✓ Yes: strongest defense |
| Prevents corporate address impersonation | ✗ No | ✗ No | ✓ Yes | ✓ Yes |
| Trust level | ★ Entry | ★★ Professional | ★★ Corporate | ★★★ Maximum |
| CA/B Forum S/MIME BR compliant | ✓ | ✓ | ✓ | ✓ |
| Get started | Buy Basic | Buy IV | Buy OV | Buy Sponsor |
Find your S/MIME certificate in two questions
Question 1 of 2
Common scenarios: which certificate applies?
| Scenario | Recommended certificate |
|---|---|
| Individual encrypting personal email for privacy | Basic S/MIME → |
| Solicitor signing client engagement letters | IV S/MIME → |
| Doctor signing patient communications | IV S/MIME → |
| Company’s support@ or billing@ address | OV S/MIME → |
| HR department signing employment contracts | OV S/MIME → |
| CEO or CFO signing board-level communications | Sponsor S/MIME → |
| Sales director sending proposals with company backing | Sponsor S/MIME → |
| Regulated industry employee (finance, healthcare, legal) | Sponsor S/MIME → or IV depending on context |
| Automated system emails (no-reply@, notifications@) | OV S/MIME → |
What every S/MIME certificate requires
WebTrust-audited S/MIME certificates from an accredited CA
WebTrust for S/MIME BR (BDO)
Audited annually by BDO: SSL.com is a WebTrust-certified CA for S/MIME Baseline Requirements
CA/B Forum S/MIME BR compliance
All certificates issued under the CA/B Forum S/MIME Baseline Requirements: the global standard
Enterprise-grade PKI
Full-service support
From certificate selection to installation guidance and renewals: SSL.com supports the full lifecycle
API & automation
S/MIME certificates available via the SSL.com SWS API for enterprise bulk issuance and automation
Compare S/MIME certificate validation levels
All S/MIME certificates from SSL.com include email signing and encryption. Validation level determines what identity is verified and embedded in the certificate.
