Compliance
What is One-Click Unsubscribe (RFC 8058)?
A standard that lets a recipient unsubscribe with a single click, with no confirmation page or login, via an automated POST request.
Defined in RFC 8058, one-click unsubscribe combines a List-Unsubscribe header containing an HTTPS URL with a List-Unsubscribe-Post: List-Unsubscribe=One-Click header. When the recipient clicks the inbox-native unsubscribe button, the mailbox provider sends an HTTP POST to that URL and the sender must complete the opt-out without requiring any further action. Under Gmail and Yahoo rules the request must be honored within two days.
Why it matters for cold email
Gmail and Yahoo require functional one-click unsubscribe for bulk senders, and honoring it within two days is part of staying off their throttle and block lists. For cold outreach, an effortless opt-out is the pressure-release valve that keeps annoyed recipients from hitting Report Spam, the single most damaging signal to sender reputation.
Related terms
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