SMS has one of the highest engagement rates of any marketing channel — open rates routinely top 90%. But since carriers rolled out A2P 10DLC (Application-to-Person 10-Digit Long Code) registration, sending marketing texts without proper registration and consent is a quick way to get messages blocked or fined.
What is A2P 10DLC?
A2P 10DLC is the carrier-approved framework for businesses sending application-to-person text messages over standard 10-digit phone numbers in the United States. It replaced the grey-area practice of sending high-volume marketing SMS from regular numbers, giving carriers visibility into who is messaging and what they're sending.
Every business now registers a Brand (your business identity) and a Campaign (the type of messaging you send). Carriers use this to score trust and apply appropriate throughput and limits.
Consent is non-negotiable
Under the TCPA, you need prior express written consent before sending marketing text messages. That means a clear opt-in — not a pre-checked box, not consent buried in terms. The person must actively agree to receive SMS marketing, and you should capture what they agreed to and when.
- Use a clear, unambiguous opt-in checkbox or keyword (e.g. text JOIN to 12345).
- Disclose that message and data rates may apply.
- State the message frequency (e.g. 'up to 4 messages per month').
- Tell users how to opt out (STOP) and get help (HELP).
Every message needs an exit
Carriers and the CTIA require that recipients can stop messages at any time. Honor STOP, STOP ALL, UNSUBSCRIBE, CANCEL, and END immediately, and process HELP requests with your support info. Make the opt-out path obvious in your program, not just the fine print.
Compliance isn't a roadblock to SMS marketing — it's the foundation that keeps your messages delivered and your brand trusted.
Keep your privacy policy current
Your privacy policy must clearly describe your SMS practices: what you collect, how you use it, that you don't sell mobile information, and how users can opt out. A vague policy won't pass a carrier review or a regulatory inquiry. Keep it specific and keep it updated.