What is 10DLC?
The US carrier registration system that standard local phone numbers must pass through before they can send business SMS at volume.
10DLC — 10DLC (ten-digit long code) is the US carrier framework for sending application-to-person SMS from standard local numbers. It requires registering the sending business and each messaging campaign before traffic is allowed. Unregistered traffic is filtered or blocked.
Why it matters
Standard ten-digit local phone numbers were built for person-to-person calls and texts. Not for a business sending application-generated messages to many recipients. 10DLC is the framework US carriers built to allow that kind of application-to-person traffic on local numbers. It is allowed only after the sending business and each messaging campaign have been registered with the carrier network. Registration establishes who is sending, what kind of messages they plan to send, and at what volume.
The registration step is not optional in practice. Traffic from an unregistered number is filtered or blocked outright by carriers. A business that skips it will see messages simply fail to arrive, with no warning. The process itself is not instant. It typically takes anywhere from a few days to a few weeks, depending on the carrier and the type of campaign. That detail catches teams off guard when they buy a number and expect to text from it the same day.
How 10DLC registration works
- 1
Register the business
The sending company is registered with identifying and verification details.
- 2
Register the campaign
Each type of messaging use case, such as marketing or appointment reminders, is registered separately.
- 3
Carriers review the registration
The review sets the number's trust level and throughput limits.
- 4
The number is provisioned for sending
Once approved, the local number can send application-to-person traffic at its approved volume.
- 5
Traffic is monitored ongoing
Carriers continue to filter traffic that does not match the registered campaign type.
The mistake to watch for
Questions
- How is 10DLC different from a toll-free number?
- 10DLC covers standard local numbers registered for application-to-person SMS through the brand and campaign process described here. A toll-free number uses a separate verification process specific to toll-free numbers rather than the 10DLC framework.
- How long does 10DLC registration take?
- It varies by carrier and campaign type. Registration commonly takes anywhere from a few days to a few weeks. Start it well before a launch date, not on it.
- What happens if a number is not registered?
- Carriers filter or block traffic from unregistered numbers. Messages fail to reach recipients, and the sender gets no explicit error at send time.