Definition
One-click unsubscribe refers to the List-Unsubscribe and List-Unsubscribe-Post headers that enable email clients — particularly Gmail — to display a visible unsubscribe button near the sender name. When clicked, the recipient is unsubscribed immediately without being redirected to a website or having to log in.
Google and Yahoo made one-click unsubscribe mandatory for bulk senders (sending over 5,000 emails per day to Gmail or Yahoo addresses) starting February 2024. The requirement also applies to the standard unsubscribe link in the email body, which must process the opt-out within two days.
Implementation
| Header | Purpose | Example |
|---|---|---|
| List-Unsubscribe | Provides the unsubscribe URL or mailto | <https://example.com/unsubscribe> <mailto:unsub@example.com> |
| List-Unsubscribe-Post | Signals one-click support | List-Unsubscribe-Post: List-Unsubscribe=One-Click |
Best Practices
- Implement one-click unsubscribe headers in all marketing emails
- Process unsubscribe requests immediately, not within the 2-day window
- Do not require login or additional steps after clicking unsubscribe
- Send a confirmation email only if the subscriber opted in to receive one
- Combine with a preference centre link for users who want options instead of full unsubscribing
- Test headers regularly to ensure they render correctly in Gmail, Yahoo, and Outlook.com
Frequently Asked Questions
Bulk senders who fail to implement one-click unsubscribe risk having their email rejected or filtered to spam by Gmail and Yahoo. Non-compliant senders may experience significant deliverability drops. Google announced it would begin enforcing this requirement in February 2024.
No. You must still include an unsubscribe link in the email body as required by CAN-SPAM (US) and other regulations. The one-click header is an additional requirement that makes unsubscribing easier from within the email client interface, particularly on mobile where finding the footer link is harder.