Envelope-To: Understanding the SMTP Recipient Address

Envelope-to is the SMTP-level recipient address used during delivery. Learn how it differs from headers and why it matters for routing.

Envelope-to is the recipient address used at the SMTP level during delivery, set via the RCPT TO command. It can differ from what appears in message headers, especially in BCC scenarios.

Understanding envelope-to helps debug routing problems, aliasing, and forwarding rules. It also matters for systems that apply per-recipient policies during SMTP acceptance.

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It just works like magic.

Envelope-To: Understanding the SMTP Recipient Address

It just works like magic.