A2P 10DLC Overview: What It Is and Who Runs It
A2P 10DLC is the US carrier framework that requires businesses to register their identity and message types before automated SMS/MMS from a local number is allowed. Here's the data model and the roles behind it.
A2P 10DLC stands for Application-to-Person messaging over a 10-Digit Long Code — a standard local phone number. It is the US carrier-mandated framework requiring businesses to register their identity and their message types before automated SMS/MMS from local numbers is allowed to flow.
The three major carriers — AT&T, T-Mobile, and Verizon — introduced it to curb spam and phishing and to make every commercial sender traceable to a verified business. P2P (person-to-person) texting from your personal phone is unaffected; this is strictly about application-driven traffic.
Why carriers built it
Before 10DLC, businesses sent A2P traffic over ordinary local numbers indistinguishable from personal texting. That made spam unattributable and gave carriers no way to throttle bad actors without hurting legitimate senders. 10DLC fixes that by tying every commercial message back to a vetted Brand and an approved Campaign, so carriers can score trust, meter throughput, and block abuse at the source.
Who’s who: the ecosystem roles
You will deal with several distinct parties. They are easy to confuse because some companies play more than one role.
| Role | What it is | Examples |
|---|---|---|
| CSP (Campaign Service Provider) | Registers brands and campaigns in TCR on a business’s behalf. Brands cannot register directly with TCR. | Twilio, Telnyx, Bandwidth, Plivo, Vonage, Sinch, Bird |
| DCA (Direct Connect Aggregator) | Carrier-connected aggregator that performs the actual campaign vetting/approval and charges the $15 vetting fee | Bandwidth and other tier-1s |
| Vetting provider | Third party that scores brand legitimacy (produces the Trust Score) | Aegis Mobile, WMC Global; Campaign Verify (political) |
| MNO (carrier) | Sets throughput, applies content filters, blocks traffic | AT&T, T-Mobile, Verizon, US Cellular |
The Campaign Registry (TCR) is the central clearinghouse that stores verified Brand and Campaign records and distributes them to carriers and vetting partners. It is operated as a private registry. The single most important thing to internalize: brands cannot register directly with TCR — every registration flows through a CSP.
The data model is hierarchical
Brand business identity, vetted → Trust Score
└── Campaign use case: Marketing / 2FA / Account Notification / …
└── Phone Number(s) attached at campaign level; via a Messaging Service in Twilio
A few rules fall out of this structure that shape everything downstream:
- One Brand → many Campaigns. One Campaign → many numbers — except Sole Proprietor brands, which are limited to one number per campaign.
- Each carrier reviews and approves separately. A campaign can be approved on T-Mobile and still pending on AT&T.
- Brand-level items: identity verification, Trust Score , and the T-Mobile daily cap (shared across all of that brand’s campaigns and numbers).
- Campaign-level items: the use case, sample messages, opt-in flow, and AT&T’s per-campaign throughput.
This split matters when you plan throughput: T-Mobile meters at the brand level, AT&T at the campaign level, and Verizon at the number level. See Trust Score and throughput for the full mechanics.
What you actually have to do
At a high level: create a customer profile with your CSP, register your brand, optionally pay for vetting to raise your Trust Score, register a campaign, then send. The full sequence — with timelines and the sole-proprietor OTP deadline — is in the registration guide.
If you don’t have an EIN, you’re on the Sole Proprietor path, which trades full vetting for hard volume caps. If your campaign gets rejected, the rejection reasons page covers the fixes — and the $15-per-resubmit reality.
Next: Registration guide →