If you send marketing email to even a handful of people, a US law called CAN-SPAM applies to you. The good news: the rules are short, they are mostly common sense, and a small list can follow them with a few settings in your email service. This is general information, not legal advice, and rules differ for subscribers in other countries.
What CAN-SPAM Actually Covers
The Federal Trade Commission (FTC) enforces the CAN-SPAM Act. It applies to commercial email, meaning messages whose primary purpose is to advertise or promote a product or service. That includes a newsletter that pitches your ebook. It does not matter whether the list is large or small, or whether recipients opted in. As of October 2026, the FTC says each separate email that breaks the rules can carry a penalty of up to $53,088.
The Core Rules in Plain Words
The FTC’s compliance guide lists eight requirements. These are the ones a solo business touches most often:
- Be honest about who you are. The “From,” “To” and “Reply-To” details must be accurate and identify the sender.
- Keep subject lines truthful. The subject has to match what is inside. “Your receipt” on a sales pitch is a problem.
- Say it is an ad when it is one. Promotional messages must clearly disclose that they are advertisements.
- Include a valid postal address. A street address, a USPS-registered P.O. box or a registered private mailbox all qualify. Many solo owners use a mailbox service rather than a home address.
- Offer a clear way to opt out. Explain how, and make it easy, such as a working unsubscribe link or a reply address. Your spam filter must not block those requests.
- Honor opt-outs fast. Process requests within 10 business days, keep the opt-out working for at least 30 days after you send, and never charge a fee or ask for more than an email address.
- Do not sell or share opted-out addresses. The FTC makes a narrow exception for a company helping you comply.
Where Small Senders Slip
Most mistakes are not scams, they are leftovers. A footer missing the address after a template change. An unsubscribe request sitting in a personal inbox for three weeks. A “Re:” subject line on a first message. Another trap is handing the job to someone else: the FTC notes you cannot contract away your legal responsibility, so if a partner sends email promoting your product, both of you may be on the hook.
A reputable email service handles the unsubscribe link and the address footer automatically, which is one reason to use one instead of sending from your regular inbox. Authentication matters too, though it is a separate issue; our guide to SPF, DKIM and DMARC covers it.
Other Rules You May Need
CAN-SPAM is the US baseline. If people in the EU or other regions subscribe, their local rules can be stricter, often requiring clear consent up front. Your choice between single and double confirmation matters there; see our post on double opt-in vs. single opt-in. Check your own situation with an official source or a qualified professional.
Do this today
Open the most recent email you sent to your list, or your email service’s default footer. Check four things: your real name or business name in the From line, a working unsubscribe link, a valid postal address, and a subject line that matches the content. Fix whatever is missing, then send yourself a test. It takes about 15 minutes.
More on Totally Relentless
- Why Your Side Business Needs an Email List, Even a Tiny One
- How to Write Email Subject Lines People Actually Open
