United States SMS messaging regulations and restrictions

All SMS messaging in The United States of America is governed by the CTIA – The Wireless Association. Strict rules are in place to regulate USA messaging, and it’s important to work closely with your sales advisor to ensure your program is compliant with the latest regulations at all times.

Note that Federal Communications Commission (FCC) bans SMS messages sent to a mobile phone using an auto-dialer unless prior consent has been received by the user or the message is sent for emergency reasons. The ban applies to all numbers, including those not specified on the Do Not Call list.

Short codes are ideal for marketing messages, any form of bulk messaging, or messages containing URLs. The regulations for US short codes will be provided to you once your application is approved. You can also view the CTIA Short Code Monitoring Handbook. Long numbers are typically used for sending person-to-person communication like appointment reminders, alerts, and announcements. That means you may use it to send messages to customers, employees, and other individuals with an interest in your business. The restrictions below only apply to long numbers.

Our expert advisors are up to date with the latest US messaging regulations and can guide you as you set up and maintain your program. Email expertadvisors@clickatell.com to get started.


Restriction  DescriptionDND existsNoTime restrictionsNoInternational vs local splitNoLocal trafficN/AInternational trafficN/AGeneral content restrictions

  • Harmful content is not allowed

  • URLs have a high probability of being blocked

  • Recipients need to consent to receive marketing communication in writing (i.e. email or other) before you start sending marketing messages to them

  • The symbol for Euro (€) is not supported

Content registration requiredNoOpt-out instructions required


  • Each marketing SMS must contain an opt-out option

  • Two-way numbers are mandatory to ensure that people can unsubscribe

Sender ID regulations

  • All messages must either be sent and delivered with a US short code or long code

  • Message volumes for each long number are limited to 5,000 per day. Exceeding this limit could result in your number being blocked

Sender ID documentation requiredN/ACountry supports MNPYes




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