US carriers require businesses to complete carrier registration before sending messages or displaying a business name on outbound calls. Due to US carrier regulations, messaging and CNAM (Caller Name) features are not enabled for US phone numbers until A2P 10DLC registration is completed.
This article explains what US carrier registration is, who needs it, and when it’s required in DialLink.
What is A2P 10DLC?
A2P 10DLC (Application-to-Person 10-Digit Long Code) is a US messaging standard that allows businesses to send SMS and MMS messages using standard 10-digit phone numbers.
This standard is enforced by major US carriers, including AT&T, T-Mobile, and Verizon, to reduce spam and protect consumers from fraudulent messaging. Compared to traditional long-code SMS, A2P 10DLC:
improves message delivery rates,
reduces carrier filtering,
allows businesses to use regular US phone numbers for messaging.
A2P 10DLC registration is also required to enable CNAM (Caller Name*) on US phone numbers.
This is a regulatory requirement. While we’re here to help, approval timelines are outside of DialLink’s control. To help avoid delays or rejection, please ensure all required information is submitted accurately.
What is CNAM?
CNAM (Caller Name) is the business name that may appear on the recipient’s device when you place an outbound call to a US phone number.
CNAM display depends on US carrier databases and is not guaranteed in all cases. However, completing US carrier registration is a mandatory prerequisite for CNAM enablement.
Without registration, outbound calls from US numbers may show:
an empty caller name,
a generic label,
or be flagged as potential spam.
Who needs to register?
You must complete US carrier registration if you:
Send SMS or MMS messages to US phone numbers using a 10DLC number.
Want your outbound US calls to display your business name via CNAM.
This applies to:
businesses with a US Tax ID (EIN)
sole proprietors or individuals without an EIN
Any organization sending application-generated messages (A2P messaging) to US numbers is required to complete A2P 10DLC registration process.
Why is registration required?
Registration is required to comply with US carrier policies and to ensure reliable communication. Without registration:
SMS and MMS messages to US numbers are blocked.
Messaging traffic may be filtered or rejected.
CNAM cannot be enabled.
As of August 31, 2023, users with unregistered or unverified phone numbers can no longer send messages to US phone numbers through any provider, including DialLink.
Who must complete A2P 10 DLC registration through DialLink?
Any DialLink customer sending messages to US phone numbers must complete carrier registration, regardless of whether they have an EIN.
Important limitations
Only paid DialLink accounts can access US carrier registration settings.
Trial accounts must upgrade to a paid plan before registering. For more information about trial limitations, please refer to this article.
How to submit A2P 10DLC registration through DialLink
Registration can be performed directly in your DialLink tenant. DialLink provides a built-in flow that guides you through the required steps. To complete registration:
Open your DialLink workspace > Settings.
Go to the Trust tab.
Start the US carrier registration process.
Approval status is tracked directly in DialLink.
For step-by-step instructions, see: How to register for A2P 10DLC in DialLink.
For a full breakdown of what information is required for registration, see: Information required for A2P 10DLC registration.
What happens after the registration has been approved?
Once your registration is approved:
messaging to US numbers is enabled
delivery rates improve and filtering risk is reduced
CNAM can be enabled for outbound US calls
Messaging limits and available features depend on whether you register as a business with an EIN or as a sole proprietor.
Learn more: A2P 10DLC fees, limits, and benefits in DialLink
Tips for successful registration
To improve your messaging reputation and reduce the risk of spam labeling:
Register your phone number with the Free Caller Registry
Ensure all information is accurate and consistent
Avoid reusing the same phone numbers across multiple registration requests
For ported phone numbers, make sure the porting request is complete and the phone number is fully functional before submitting an A2P 10DLC registration request
What’s next?
If you’re ready to proceed:
Enable CNAMs* (Caller ID names) for your phone numbers in DialLink
Completing US carrier registration ensures your messages reach customers reliably and your calls display your business identity whenever possible.
* In DialLink, Caller Name may also be referred to as Caller ID name.