A2P 10DLC
also 10DLC · Application-to-Person 10DLC
A US carrier registration standard for sending application-to-person SMS over standard 10-digit long codes, requiring brand and campaign registration to avoid filtering.
Analogy
Like getting a business license before you're allowed to text customers at scale through US carriers.
Why it matters
Unregistered or misregistered 10DLC kills SMS deliverability, so completing it correctly is essential before any GHL texting automation goes live.
In practice
You register a client's EIN as a brand and submit a campaign use-case so their workflow SMS messages stop getting blocked.