Infrastructure
What is Return-Path?
The address where bounces and delivery failures are sent, and the domain SPF authenticates against.
The Return-Path, also called the bounce address, is set during the SMTP transaction and recorded in a header by the receiving server. It is the domain checked for SPF authentication and the destination for non-delivery reports. It is distinct from the visible From address, and aligning its domain with the From domain is one of the two ways to satisfy DMARC.
Why it matters for cold email
A custom, aligned Return-Path strengthens SPF authentication and DMARC alignment for cold email and ensures bounces flow back to a mailbox you can process. Routing bounces to a domain you control lets you suppress invalid addresses quickly and protect your sender reputation.
Related terms
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