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What is CAN-SPAM?

By Mailneo Team|

CAN-SPAM (Controlling the Assault of Non-Solicited Pornography And Marketing) is the U.S. federal law that sets rules for commercial email. It requires truthful headers, a physical postal address, and an opt-out mechanism that works within 10 business days.

Why It Matters

Violating CAN-SPAM can cost up to $51,744 per email — that's per message, not per campaign. The FTC enforces it, and they've gone after companies of all sizes. Beyond the legal risk, CAN-SPAM compliance is table stakes for any email program. If your emails lack an unsubscribe link or use deceptive subject lines, you're breaking the law.

How It Works

CAN-SPAM applies to any commercial message — meaning any email whose primary purpose is advertising or promoting a product or service. Here's what it requires:

  • No misleading header information (From, To, Reply-To must be accurate)
  • No deceptive subject lines
  • Identify the message as an ad (if it is one)
  • Include your physical postal address
  • Provide a clear way to opt out
  • Honor opt-out requests within 10 business days
  • Monitor what third parties do on your behalf — you're responsible for their compliance too

One thing that surprises people: CAN-SPAM doesn't require prior consent to send. It's an opt-out law, not an opt-in law. That's a key difference from GDPR and CASL, which are stricter.

Quick Tips

  • Process unsubscribes within 24 hours, not 10 days. Just because the law gives you 10 days doesn't mean you should take them — subscribers expect instant removal.
  • Your physical address can be a PO Box or registered commercial mail receiving agency. You don't need to publish your home address.
  • If you have affiliates or partners sending email on your behalf, you're legally responsible for their compliance. Audit them.

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