Compliance
Opt-out
When a user withdraws permission to receive emails, typically by clicking an unsubscribe link.
Definition
Opt-out (or unsubscribe) is when a recipient withdraws their permission to receive emails. By law (CAN-SPAM, GDPR), senders must provide a clear, working opt-out mechanism and honor requests promptly - typically within 10 business days but best practice is immediate. Using list-unsubscribe headers helps recipients unsubscribe easily.
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