List-Unsubscribe header
A header that tells mailbox apps which web or email address can unsubscribe the recipient, so they may show their own control.
See it
What it is
List-Unsubscribe is a message header that advertises one or more ways to leave a mailing list, usually an HTTPS URL and a mailto URL inside angle brackets. A supporting mailbox client can use those methods to put an Unsubscribe control beside the sender instead of making the reader hunt through the footer.
Add it to newsletters and promotional mail, with a recipient-specific token that resolves to the correct list membership. Keep the visible footer link too. RFC 2369 defines the header; RFC 8058 adds List-Unsubscribe-Post for a true one-click HTTPS POST with no landing page interaction. Gmail and Yahoo have required one-click unsubscribe from bulk senders since February 2024, so at volume this is a rule rather than a courtesy.
The header does not guarantee a button. Gmail, Apple Mail, and other clients decide whether to expose it using their own support and trust signals. A plain List-Unsubscribe HTTPS link may open a page, while RFC 8058 one-click requires the companion POST header and DKIM coverage. Whichever method you advertise must actually suppress the recipient, not drop them onto a login screen.
Ask AI for it
Add unsubscribe metadata to our Nodemailer marketing messages using its 'headers' property. Emit 'List-Unsubscribe: <https://example.com/unsubscribe/{signedToken}>, <mailto:unsubscribe@example.com?subject=unsubscribe>' according to RFC 2369, and add 'List-Unsubscribe-Post: List-Unsubscribe=One-Click' for the RFC 8058 HTTPS POST flow. Make the token HMAC-signed for the recipient and list, make the POST handler unauthenticated and idempotent, and ensure DKIM signs both header fields. Keep a visible footer link, exclude transactional messages, and include a raw-message test plus an HTTP test proving a repeated one-click POST returns 200 and leaves the address suppressed.