RexaThe short answer
A2P 10DLC governs business messaging from standard local numbers. It matters to voice AI because most voice deployments send some SMS — appointment confirmations, callback links, opt-out confirmations — and unregistered traffic is filtered or blocked by carriers. Registration is a prerequisite, not an optimisation, and it takes time to clear.
In detail
Registration has two stages. A brand record identifies the legal entity, typically requiring legal name, tax identification number, address and contact details, and for publicly traded companies a stock symbol. A campaign record then describes the specific messaging use case: what the messages say, how consent is obtained, and sample message content. Both are submitted to the Campaign Registry and vetted before throughput is granted.
Once approved, the brand and campaign determine what the numbers associated with them are permitted to do. Throughput limits and per-day caps are assigned based on the vetting outcome, and messages that do not match the registered use case can be filtered. Sending unregistered A2P traffic from a long code results in blocking rather than a warning.
The framework matters to voice teams because a mixed-channel workflow inherits both rule sets. A voice campaign that also texts must satisfy A2P registration for the messaging leg and calling-time and consent rules for the voice leg — and the opt-out captured on either channel has to suppress both, which is a data-model question more than a telecom one.
How Rexa handles it
Rexa models 10DLC registration explicitly, with brand and campaign records tracked through to Campaign Registry identifiers. Submissions are validated before they leave the platform: a brand missing tax id, email or phone is rejected, a public-profit entity must carry a stock symbol, and campaign content must include non-empty sample messages — so malformed registrations fail locally rather than after a slow external rejection.
Compliance overviewRelated terms
STIR/SHAKEN
STIR/SHAKEN is a framework of standards by which carriers cryptographically sign outbound calls to attest to the legitimacy of the calling number.
TCPA
The TCPA is a US federal statute restricting telemarketing calls, automated dialling, prerecorded and artificial voice messages, and unsolicited texts.
Opt-out keyword
An opt-out keyword is a word or phrase that, when spoken or sent by a recipient, is treated as a request to stop being contacted.
DID
A DID is a telephone number assigned to an organisation that routes an inbound call directly to a specific destination without passing through an operator.