What is A2P 10DLC and Why It Matters for Business SMS

Executive Summary

If your business sends SMS messages to phone numbers in the United States, recent changes in carrier regulations directly impact you. US mobile carriers now require all businesses to register their SMS campaigns under a system known as A2P 10DLC. This registration is mandatory for any organization using a standard 10-digit phone number to send application-to-person (A2P) text messages — meaning any SMS messages sent from a business to a customer or member of the public.

This requirement is designed to cut down on spam and fraud, while ensuring that businesses using SMS for legitimate purposes can continue to reach their customers reliably.

What is A2P 10DLC?

A2P stands for Application-to-Person messaging, referring to texts sent from software platforms (like VoIPstudio) directly to consumers’ phones.

10DLC refers to 10-digit long codes — the standard local phone numbers many businesses use for sending texts. These are different from short codes (5 or 6-digit numbers) or toll-free numbers.

Why Did Carriers Introduce This Requirement?

US carriers, including AT&T, T-Mobile, and Verizon, introduced A2P 10DLC registration to combat increasing amounts of spam and unwanted messages. By requiring businesses to register both their brand (company) and campaigns (specific use cases for texting), carriers can better identify and approve legitimate messages while filtering out bad actors.

This system helps protect end-users while also ensuring that businesses who follow the rules can reliably reach their audiences without unnecessary filtering or blocked messages.

Who Needs to Register?

Any business or organization that sends SMS messages to US phone numbers from 10-digit numbers needs to register. This applies to a wide range of use cases, including:

• Marketing promotions
• Appointment confirmations
• Delivery notifications
• Customer support follow-ups
• Two-factor authentication (2FA) codes

Even if your messages are strictly transactional or informational, registration is still required.

What Information is Required for Registration?

The registration process involves submitting basic information about your business and your intended SMS usage. This typically includes:

• Your company’s legal name
• Your tax ID (EIN if you are a US business)
• Your business address and industry
• A description of the types of messages you plan to send
• Sample message content
• Details on how recipients opt in to receive messages from you

What Happens if You Don’t Register?

Unregistered SMS traffic to US numbers may:

• Be blocked entirely by carriers
• Experience delivery delays or reduced success rates
• Incur higher per-message fees

Simply put: if you want to ensure your messages reliably reach your customers, registration is no longer optional.

Common Misconceptions

• “I only send a few texts per month, so I don’t need to register.”
  This is false — registration is required regardless of message volume.
  
• “My customers gave me consent, so that’s enough.”
  While customer consent is critical, it does not replace the need for formal campaign registration.
• “This only applies to marketing messages.”
  Incorrect — transactional and informational messages must also be registered.

Benefits of Compliance

While the new requirements may feel like an administrative hassle, there are tangible benefits to participating in the A2P 10DLC program:

• Improved message deliverability
• Reduced risk of filtering or blocking
• Consistent compliance across all US carriers

The Role of VoIPstudio

As your communications provider, VoIPstudio can guide you through this process. We’ve created a simple registration form for you to complete, which ensures that all the necessary information is collected and submitted to the carriers on your behalf.

You’ll receive further instructions directly from our team to confirm once your campaign is successfully registered and approved.

Final Thoughts

A2P 10DLC is a carrier-driven requirement that impacts every business sending SMS messages to the US market. While it may seem like another layer of compliance, it’s ultimately designed to protect both consumers and businesses by ensuring that the SMS channel remains trusted and effective.

If you have any questions about this process, VoIPstudio’s support team is ready to assist.