Who Governs A2P: The Regulatory Bodies
A2P in the US isn't one license from one agency — it's a stack of overlapping authorities. Here's each body, what kind of power it actually has, and what it controls.
There is no single “A2P regulator.” Getting a US brand qualified to text and call means satisfying a federal agency, an industry trade group, a private registry, a number administrator, three mobile carriers, and an industry traceback consortium — each with a different kind of authority. The most important distinction: only the FCC makes binding law. Everyone else either operates a registry, publishes “best practices” the carriers choose to enforce, or filters traffic on its own network. That difference dictates who you appeal to when something goes wrong.
Who does what
| Body | Type | Role |
|---|---|---|
| FCC | Government regulator | Enforces the TCPA (47 U.S.C. 227 / 47 CFR 64.1200), mandates STIR/SHAKEN , and runs the RMD |
| CTIA | Wireless trade association | Publishes the (non-binding, carrier-enforced) Messaging Principles & Best Practices; governs Branded Calling ID (BCID ) |
| TCR (The Campaign Registry) | Private registry (Kaleyra / Tata) | The central 10DLC brand & campaign registry; coordinates vetting and the Trust Score |
| Somos | Neutral number administrator | Toll-free number administration + TSS Registry (text enablement); runs the U.S. Short Code Registry |
| Mobile carriers (MNOs) | Private (AT&T, T-Mobile, Verizon) | Set throughput and trust behavior; do the actual filtering and blocking |
| ITG (Industry Traceback Group) | USTelecom-led consortium | The FCC-designated Traceback Consortium under the TRACED Act |
For the dated history of what each of these changed in 2024–2026, see the change tracker.
FCC — the only one that makes law
The Federal Communications Commission is the single government regulator in the stack, and the only body whose rules carry the force of federal law. It enforces the TCPA through 47 CFR 64.1200, mandates STIR/SHAKEN caller-ID authentication on IP voice networks, and operates the RMD where every voice, intermediate, and gateway provider must certify its robocall-mitigation status. When the FCC acts, the effect is national and binding immediately on publication — the February 2024 ruling that AI-generated voices are “artificial” under the TCPA, for example, took effect the day it was issued.
The FCC is also the body that gives the TCPA its teeth indirectly: the statute carries a private right of action, so most enforcement actually happens in court, brought by recipients, not by the agency. The FCC’s own enforcement tends to land on providers — revoking RMD certifications and issuing forfeitures.
See /regulations/fcc/ for the full breakdown of the FCC’s three roles.
CTIA — powerful, but technically non-binding
CTIA is the wireless trade association — the carriers’ own industry group. Its flagship document, the Messaging Principles & Best Practices (latest revision May 2023), is the de facto rulebook for US business texting: opt-in standards, STOP/HELP handling, the privacy-policy clause, and the SHAFT prohibited-content list all trace back to it. CTIA also published a separate Messaging Security Best Practices document in October 2025, and it governs Branded Calling ID (BCID ) through its subsidiary, BCID, LLC.
See /regulations/ctia/ for the detail.
TCR — the registry, not a regulator
The Campaign Registry is a private registry (owned by Kaleyra / Tata) that the carriers designated as the central clearinghouse for 10DLC. It stores verified Brand and Campaign records, coordinates the secondary vetting that produces the Trust Score, and distributes that data to the carriers and vetting partners. TCR sets no consent law and runs no network — it is plumbing. Brands cannot register with it directly; registration flows through a Campaign Service Provider (CSP). See the 10DLC overview and fees.
Somos — toll-free and short-code administration
Somos is the neutral administrator for two of the three number types. It runs toll-free number administration and the TSS Registry that text-enables toll-free numbers (the backbone of toll-free verification), and it operates the U.S. Short Code Registry at usshortcodes.com where short codes are leased. Like TCR, Somos administers a system rather than regulating conduct.
The mobile carriers (MNOs) — where blocking actually happens
AT&T, T-Mobile, and Verizon are private companies, not regulators — but they own the last mile, so they are where every rule above gets applied. They set throughput (each on its own model — see trust score & throughput), they enforce CTIA’s best practices as conditions of carriage, and they do the actual filtering and blocking. Since February 1, 2025 the carriers block 100% of unregistered 10DLC traffic outright. Each carrier also reviews 10DLC campaigns separately, which is why approvals can land on different days.
ITG — tracing illegal calls to their source
The Industry Traceback Group (ITG ) is a USTelecom-led consortium designated by the FCC as the official Traceback Consortium under the TRACED Act. It doesn’t make rules or block traffic; it traces suspected illegal calls back through the chain of providers to their point of origin, then hands that evidence to the FCC and law enforcement. Its work feeds directly into the FCC’s RMD enforcement — its live-call identifications jumped from 607 in 2023 to 1,408 in 2024, the data behind the 2025 wave of certification revocations.
How they fit together
- Legality of the message or call → FCC / TCPA (binding law, private right of action).
- Whether carriers will deliver it → CTIA best practices + per-carrier filtering (enforced, not legislated).
- Registration plumbing → TCR (texting brands/campaigns), Somos (toll-free, short codes).
- Caller-ID trust on voice → FCC (STIR/SHAKEN mandate + RMD), CTIA (BCID branding).
- Catching bad actors → ITG traceback → FCC enforcement.
Next
- Change tracker — every dated change since 2024 with current status.
- FCC — TCPA, STIR/SHAKEN, and the RMD in depth.
- CTIA — the carrier-enforced messaging rulebook.
- TCPA — the law that drives all of it.