The CAN-SPAM Act: what UK shops owe the US customers on their list
The US law on commercial email. It's looser than UK law on consent, more specific on a few details, and a UK list can still trip over those.
- 013CAN-SPAM Act
- A U.S. law that sets rules for commercial email, establishing requirements for commercial messages and giving recipients the right to have you stop emailing them.
- Enforced by
- The Federal Trade Commission, the FTC
- Consent model
- Opt-out: you can email first, but must stop when asked
- Opt-out deadline
- Ten business days, and the unsubscribe must keep working for at least thirty days after sending
- Penalties
- Counted per email that breaks the rules
What CAN-SPAM asks of every marketing email you send to the US
The FTC's own compliance guide is short, readable and better in the original. In plain terms, every commercial email has to do six things.
- Carry honest header details, so the from name, reply-to and routing identify you
- Use a subject line that matches what's inside
- Make clear it's an advertisement, though the law leaves room on how
- Include a valid postal address for your business
- Explain clearly how to opt out of future emails
- Honour opt-outs within ten business days, and don't sell or transfer the address afterwards
One line in the guide catches brands out: you can't contract away your legal responsibility. Hire an agency to send for you and you can both be held responsible. We'd rather you heard that from us.
Why a list built for UK law usually clears CAN-SPAM, and where it slips
Let's face it: the UK is the stricter of the two on consent. CAN-SPAM is opt-out, so you can email first and stop when asked, while PECR wants consent or the soft opt-in before the first marketing email to a consumer. A list built to the UK standard clears CAN-SPAM's consent bar easily, because there isn't one. Where UK lists slip is in the details.
- A footer address that's been out of date since the office moved
- A second platform or a CSV import that doesn't know who unsubscribed
- A subject line that promises one thing and sells another
- Texts, which fall under separate US rules
Mailbox providers ask for more than the law does anyway. Google's sender guidelines want a one-click unsubscribe and a visible unsubscribe link from bulk senders, whichever country they're in. This isn't legal advice, and if US customers are a big part of your list, an hour with a US lawyer is time well spent.
Which of your Klaviyo emails count as commercial under CAN-SPAM
The law turns on an email's primary purpose. The FTC's test is whether somebody reading the subject line would reasonably take it for an ad, and whether the transactional part comes first in the email.
| How it's likely to be treated | |
|---|---|
| Campaigns, newsletters and launches | Commercial: every rule applies |
| Abandoned cart and browse reminders | Treat as commercial: they're selling |
| Order and shipping confirmations | Transactional: most of the rules don't apply |
| A shipping confirmation stuffed with offers | Commercial, if the subject line sells or the order details aren't up top |
So keep transactional emails about the transaction, with the order details at the top. It keeps them on the right side of the test, and it's what customers open them for anyway.
Related terms
FAQs
Does CAN-SPAM apply to UK companies emailing American customers?
Plan on it applying to anything you send to people in the US, wherever your business is registered. A programme that already meets UK rules usually needs small changes, not a rebuild: a valid postal address in the footer, subject lines that match the email, and unsubscribes honoured inside the deadline.
Do I need permission to email US customers?
Not under CAN-SPAM, which is an opt-out law. You can send the first email without consent, as long as you follow its rules and stop when asked. But mailbox providers judge you on complaints and engagement, and a cold list lands in spam long before the FTC notices. Hold US subscribers to the UK standard.
Does CAN-SPAM cover marketing texts?
Mostly not. CAN-SPAM is about commercial email. Marketing texts in the US mainly fall under separate rules with their own consent requirements, and those are stricter about permission than CAN-SPAM is. Treat text message consent as its own thing, in the US and the UK, and get advice before you start texting American customers.
Rather we explained it on your own account?
Bring your Klaviyo account to a growth consultation. We'll walk through what this means for your numbers, in plain English, and what we'd fix first.
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