All 15 Email & Notifications questions
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Node.js › Email & Notifications

What is an unsubscribe mechanism, and what specific requirements does it need to meet for compliance with regulations like CAN-SPAM?

Intermediate

Answer

An unsubscribe mechanism lets recipients opt out of receiving future marketing emails -- CAN-SPAM (in the US) and similar regulations elsewhere require a clear, functioning unsubscribe link in every marketing email, that the opt-out request be honored within a set time period (10 business days under CAN-SPAM), and that the sender not charge a fee or require additional personal information beyond an email address to process the opt-out.
app.get('/unsubscribe', async (req, res) => {
  const { token } = req.query;
  const userId = await verifyUnsubscribeToken(token);
  await updateUserPreferences(userId, { marketingEmailsEnabled: false });
  res.send('You have been unsubscribed successfully.');
});
Real-world example A newsletter system includes a unique, tokenized unsubscribe link in the footer of every marketing email that immediately updates the recipient's preference record upon being clicked, ensuring compliance with the requirement to honor opt-out requests promptly.

Common follow-ups: Why should an unsubscribe link use a signed token rather than just a plain email address in the URL?;Does an unsubscribe request need to also apply to transactional emails, or only marketing emails?

Security;Authentication & Authorization
All 15 Email & Notifications questions