How to Get SMS Consent the Right Way (With Opt-In Language Examples)

Before a sales team sends its first marketing text, it needs the recipient's permission. Consent is what makes your texts legal, what carriers check before approving your campaign, and your first line of defense if a recipient ever complains. Here's what good consent looks like.

Why consent matters so much

Three layers of rules apply to marketing texts:

• Federal law. The Telephone Consumer Protection Act (TCPA) requires prior express written consent for many marketing texts, and violations can carry statutory damages per message.
• State laws. Several states have their own telemarketing laws, some broader than the federal rules.
• Carrier rules. Carriers expect opt-in consent for marketing messages, and your 10DLC campaign registration has to show exactly how you collect it.

The practical standard that satisfies all three: get clear, written consent before you send any marketing text.

What valid consent includes

Consent should be a clear, affirmative action by the person — checking an unchecked box, texting a keyword to your number, or signing a form — and it should tell them plainly what they're agreeing to:

• Who will be texting them (your business name)
• What kind of messages they'll get, and that they may be sent using automated technology
• How often — a specific frequency, or "message frequency varies"
• That message and data rates may apply
• How to stop (reply STOP) and get help (reply HELP)
• That consent isn't a condition of purchase
• Links to your terms and privacy policy

Keep a record of each consent: when it happened, where, the exact language shown, and the phone number provided.

Example opt-in language

For a checkbox on a web form, next to the phone number field:

"By checking this box, I agree to receive recurring marketing text messages from [Your business name] at the number provided, including messages sent using automated technology. Consent is not a condition of purchase. Message frequency varies. Message and data rates may apply. Reply STOP to opt out or HELP for help. See our Terms and Privacy Policy."

For a keyword opt-in, send a confirmation right after someone texts in:

"[Your business name]: You're subscribed to sales updates. Msg frequency varies. Msg & data rates may apply. Reply HELP for help, STOP to opt out."

Adapt the wording to what you actually send, and have counsel review it for your business.

Mistakes that void consent

1. Pre-checked boxes. Consent has to be an affirmative choice. A box that's already checked isn't one.
2. Burying it in the terms. Consent hidden in a long terms of service page isn't clear and conspicuous.
3. Requiring it to buy. Making text consent a condition of purchase is not allowed for marketing consent.
4. Buying or sharing lists. Consent given to someone else isn't consent to hear from you. Purchased lists don't come with permission to text.
5. Stretching the scope. Someone who agreed to appointment reminders didn't agree to promotions.
6. Losing the record. If you can't show when and how someone opted in, you may not be able to prove they did.

A note on recent changes

In 2025, a federal appeals court struck down an FCC rule that would have required consent to be collected for one seller at a time, before it took effect. That didn't loosen the core rule: marketing texts still need consent that clearly authorizes your business to text that person.

The short version

• Get clear, written, affirmative consent before any marketing text.
• Say who you are, what you'll send, how often, and how to stop.
• Never pre-check the box or make consent a condition of purchase.
• Keep a record of every opt-in.

When you onboard with Signilio, your opt-in process is part of 10DLC registration, and we'll work through it with you. Get in touch to start.

This article is general information, not legal advice. Consent requirements vary by message type and state and can change; have counsel review your opt-in language.