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TLS Reporting (TLS-RPT)

Security Glossary - Email Authentication

Definition: TLS-RPT (SMTP TLS Reporting) is a standard that allows mail servers to report TLS connection failures to the domain owner. By publishing a TLS-RPT DNS record, you receive reports about failed TLS connections, certificate errors, and MTA-STS policy failures from sending servers, giving visibility into email delivery security.

Why TLS-RPT Matters

TLS-RPT complements MTA-STS by providing feedback about TLS connection issues in email delivery. Without TLS-RPT, you would not know if sending servers are experiencing TLS failures when connecting to your mail servers, potentially causing email delivery problems.

The reports reveal certificate issues (expired, untrusted, wrong hostname), TLS configuration problems, and MTA-STS policy failures. This data helps you detect and fix email security issues before they cause widespread delivery failures. It is especially valuable when transitioning MTA-STS from testing to enforce mode.

TLS-RPT is straightforward to deploy - a single DNS TXT record specifying where to send reports. The reports are JSON formatted and can be processed by DMARC/email security reporting services. Like DMARC aggregate reports, they provide passive monitoring without affecting email delivery.

Checking Your Setup

A DNS health checker verifies the _smtp._tls TXT record for TLS-RPT configuration. The record format is: v=TLSRPTv1; rua=mailto:tls-reports@yourdomain.com. Reports are sent by participating email providers.

See how your site handles TLS-RPT

Check DNS Health

Frequently Asked Questions

Is TLS-RPT the same as DMARC reporting?
No. DMARC reporting covers email authentication (SPF, DKIM, alignment). TLS-RPT covers the TLS transport layer - whether the encrypted connection between mail servers succeeded. They are complementary and both should be configured.
Do I need MTA-STS to use TLS-RPT?
No. TLS-RPT reports on TLS connection failures regardless of MTA-STS. However, they are most valuable together - MTA-STS enforces TLS, and TLS-RPT tells you when enforcement causes delivery issues.

Related Terms

SMTP MTA Strict Transport Security Transport Layer Security Domain-based Message Authentication, Reporting and Conformance DMARC Aggregate Reports (rua) Email Deliverability
Disclaimer: DomainOptic provides automated informational scans only. Results do not constitute professional security advice, compliance certification, or a guarantee of security. Always verify findings independently.