Opt-out (or Unsubscribe)
Opt-out is the process by which a subscriber stops receiving emails by unsubscribing, removing their consent to further communications.
Opt-out, or unsubscribe, is how a recipient tells you to stop sending them marketing email. It withdraws their consent, and anti-spam laws in the US and Canada require you to offer it and act on it.
The usual path is an unsubscribe link in the email footer. It leads to a confirmation page or a preference center where the person can stop everything or choose which lists to keep.
What the law requires
Under the US CAN-SPAM Act, every commercial email must include a clear explanation of how to opt out. The mechanism must keep working for at least 30 days after the message is sent, and you must honor the request within 10 business days. You cannot charge a fee, ask for personal information beyond an email address, or require more than a reply email or a visit to a single web page. Once someone opts out, you cannot sell or transfer their address except to a company helping you comply. Source: the FTC’s CAN-SPAM compliance guide.
Under Canada’s CASL, commercial electronic messages generally need an unsubscribe mechanism, with limited exemptions, and you must stop sending within 10 business days of a request made through that mechanism or any other channel. Source: the CRTC’s CASL guidance.
Why it matters
Unsubscribe is a trust test. When the path is obvious and works the first time, people who no longer want your email leave quietly. When it is hidden or slow, the spam button is the next easiest option, and that complaint goes to the mailbox provider rather than to you.
Types of opt-out mechanisms
The basic pattern is a footer link that removes the address immediately. A one-click unsubscribe header lets mail clients show their own unsubscribe button. A preference center offers a partial opt-out alongside a full one. A suppression list stops a removed address from being mailed again by a later import or campaign.
Common mistakes
Requiring a login to unsubscribe. Removing the address from one list while another campaign keeps mailing it. Waiting until the next scheduled sync to apply the change. Each of these leaves a person receiving mail after they said no.