CTIA Messaging Guidelines & Pre-Send Checklist

Understand consent, opt-outs, identity and content rules to keep your A2P SMS compliant — then run the checklist before every send.

By 10dlccheck Editorial · Published · Updated · ~4 min read

Overview

The CTIA Messaging Principles and Best Practices define how businesses should send application-to-person (A2P) messages across U.S. carrier networks. They focus on consumer consent, transparency and responsible messaging behavior.

These are industry guidelines, not laws — but carriers actively enforce them alongside regulations like TCPA and FCC rules. Non-compliance leads to filtering, blocking, and potential fines.

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What changed in the 2025 update?

  • Stronger enforcement of explicit opt-in requirements
  • Mandatory brand identification in every message
  • Increased filtering for misleading or unregistered traffic
  • Closer alignment between carriers on enforcement rules
  • Obtain clear, documented opt-in before sending any messages
  • Explain message purpose and frequency at the point of opt-in
  • Do not use purchased or shared contact lists
"Text JOIN to 12345 to receive weekly updates. Msg & data rates may apply. Reply STOP to opt out."

Identity and transparency

  • Clearly identify your brand in every message
  • Use branded domains instead of generic short links (avoid bit.ly, tinyurl, etc.)
  • Ensure phone numbers match your registered business identity

Opt-out and HELP support

  • Support STOP, UNSUBSCRIBE, and CANCEL
  • Respond to HELP with support contact information
  • Process opt-outs immediately and apply them across all campaigns

Content standards

  • Avoid deceptive, illegal, or misleading content
  • Clearly state all offer terms
  • Do not use evasion tactics such as traffic splitting
  • No SHAFT content (Sex, Hate, Alcohol, Firearms, Tobacco)
  • No get-rich-quick or high-pressure financial claims

Numbers and provisioning

  • Only use numbers you are authorized to text-enable
  • Monitor shared numbers for abuse
  • Remove inactive numbers to reduce complaints
  • Do not split traffic across multiple numbers to evade detection

Mitigating filtering and blocking

  • Track opt-outs, complaints and delivery issues consistently
  • Avoid sudden traffic spikes
  • Keep messaging aligned with your registered campaign type
  • Use branded links and consistent sending patterns

Message examples

Compliant

"BrandName: 20% off this week only at brand.com/sale. Reply STOP to opt out."

  • Brand identified
  • Branded domain link
  • Clear opt-out instructions
Non-compliant

"50% OFF NOW: bit.ly/xyz123"

  • No brand identification
  • Public link shortener
  • No opt-out instructions

Pre-Send Compliance Checklist

Run through every item before sending your campaign. Progress updates as you check items off.

0 / 14 complete

Audience and consent

Message content

Links

Opt-out and help

Sending practices

Registration and records

Frequently asked questions

What are CTIA messaging guidelines?

Industry standards for consent, transparency and responsible A2P SMS messaging, maintained by CTIA — the U.S. wireless industry association.

Are CTIA rules legally required?

No, but carriers enforce them alongside legal regulations like TCPA and FCC rules. Violations can result in message filtering or account suspension.

What opt-out keywords must be supported?

STOP, UNSUBSCRIBE and CANCEL must all be supported. HELP must return support contact information.

Should I use branded links?

Yes. Branded domains improve deliverability and reduce the chance of carrier filtering. Avoid public shorteners like bit.ly, especially in first contact.

Do I need to show STOP/HELP in every message?

Single-message programs may not include it in that one message, but systems must still support those keywords. Ongoing programs should include STOP instructions in the first message.

Official references