How registration works
Sending SMS in the United States requires compliance with federal law, industry guidelines, and individual carrier rules. This page walks through the full journey from understanding the rules to maintaining your program after launch.
The registration journey [#the-registration-journey]
Understand the compliance layers
Federal law (TCPA), industry guidelines (CTIA), and carrier networks.
Choose your sender type
10DLC, short code, or toll-free.
Collect proper consent
Express consent for transactional, express written consent for marketing.
Register your sender
Brand registration, vetting, and campaign creation.
Build compliant messages
Business identification, opt-out instructions, rates disclosure.
Handle opt-outs
Honor every unsubscribe within 10 seconds.
Monitor and maintain
Track opt-out rates, delivery rates, and act on warnings.
Compliance layers [#compliance-layers]
Three overlapping layers govern SMS messaging in the United States.
| Layer | What it means |
|---|---|
| TCPA | Federal legislation that treats text messages as phone calls. Violations can trigger statutory damages of up to $500 per text, or $1,500 per willful violation. |
| CTIA guidelines | Industry guidelines maintained by the Cellular Telecommunications Industry Association. Carriers enforce these and can filter, reject, or disable non-compliant campaigns. |
| Carrier networks | Each major carrier (T-Mobile, AT&T, Verizon) reserves the right to approve, reject, or disable any campaign on their network. |
Learn moreUSA SMS compliance requirements: Consent model, opt-out rules, and carrier requirements
Consent requirements [#consent-requirements]
The type of consent required depends on what you send.
| Consent type | Required for | What it means |
|---|---|---|
| Express consent | Transactional messages, service messages, OTPs | The consumer provides their phone number and agrees to receive messages. |
| Express written consent | Marketing and promotional messages | Must include a clear disclosure, affirmative opt-in action, description of messages, opt-out instructions, and "message and data rates may apply" disclaimer. Pre-checked boxes do not count. |
Learn moreUSA messaging content requirements: Content rules, call-to-action requirements, prohibited content categories
Message requirements [#message-requirements]
Every message must include:
- Business identification (brand or company name)
- Content matching the use case the consumer consented to
- Opt-out instructions ("Reply STOP to opt out") in every marketing message
- Rates disclaimer ("Message and data rates may apply") in the first message
First message after opt-in must also include: program name, message frequency disclosure, STOP instructions, HELP instructions, and link to terms/privacy policy.
Sending hours: 8 AM to 9 PM in the recipient's local time zone.
Opt-out handling [#opt-out-handling]
When a recipient sends STOP, STOPALL, UNSUBSCRIBE, CANCEL, END, or QUIT:
- Remove from all active campaigns within 10 seconds
- Send one confirmation: "You have been unsubscribed. No further messages will be sent."
- Add to suppression list
- Only re-message if the consumer explicitly opts back in
When a recipient sends HELP, respond with: brand name, support contact, message frequency, rates disclaimer, and STOP instructions.
Ongoing monitoring [#ongoing-monitoring]
| Metric | Target |
|---|---|
| Opt-out rate | Below 2% per campaign |
| Spam complaint rate | Below 0.1% |
| Delivery rate | Monitor for drops greater than 10% |
Act immediately on: delivery rate drops, carrier suspension notices, complaint spikes, or legal notices.
Learn moreDeactivated and ported numbers: Number health maintenance and FCC daily requirements
Register a brand
Start the registration process.
Choose your number type
Compare 10DLC, short code, and toll-free.
USA SMS compliance requirements
Full compliance rules.