What Is A2P 10DLC? The Complete Guide for Businesses (2026)

If your business sends text messages to US customers from a regular 10-digit phone number, you are sending A2P 10DLC traffic. Since February 2025, US carriers block 100% of that traffic unless the sender is registered. This guide explains what A2P 10DLC is, who needs it, what it costs, and how to get through registration without the rejections that trip up most businesses.

A2P 10DLC, decoded

The name packs two concepts together:

• A2P stands for application-to-person: any message sent from software (a CRM, a booking system, a marketing platform) to a person. The opposite is P2P, person-to-person: two humans texting each other. If a computer triggers the message, it is A2P, no matter how conversational it looks.
• 10DLC stands for 10-digit long code: a standard local US phone number, as opposed to a 5–6 digit short code or a toll-free number.

Historically, businesses blasted marketing from cheap local numbers that were never meant for bulk traffic, and carriers fought back with aggressive spam filtering. A2P 10DLC is the truce: carriers created a sanctioned, registered route for business messaging over local numbers. Registered senders get reliable delivery and defined throughput; unregistered senders get blocked.

Who needs to register

Every business, nonprofit, and organization that sends application-to-person SMS or MMS to US phone numbers over a local 10-digit number, regardless of volume. That includes:

• Appointment reminders from your scheduling software
• Order and delivery notifications from your e-commerce store
• Two-factor authentication and one-time passcodes
• Marketing and promotional campaigns
• Even low-volume conversational texting sent through a CRM or texting app

There is no exemption for small senders. A solo practitioner sending 20 reminders a day needs registration just like an enterprise sending millions, though there is a cheaper Sole Proprietor path for individuals without an EIN. The only way around 10DLC registration is to use a different number type entirely; see our comparison of 10DLC, toll-free, and short codes.

How the ecosystem works

The three big US carriers (AT&T, T-Mobile, Verizon) created The Campaign Registry (TCR) as the central database of approved business senders. You rarely deal with TCR directly. Instead, your messaging provider (Twilio, for example) acts as a Campaign Service Provider (CSP) and submits your information to TCR on your behalf. Independent reviewers called Direct Connect Aggregators (DCAs) then vet campaigns before carriers accept the traffic. We break down each player in our guide to The Campaign Registry.

Registration itself has two layers:

1. Brand registration, where you identify your business: legal name, EIN, address, website. TCR verifies this against public records. Read more in our brand registration guide.
2. Campaign registration, where you describe the messages you will send: the use case, sample messages, and proof that recipients opted in. This is where most rejections happen. See how to choose a campaign use case.

What it costs

Fees are set by TCR and passed through by your provider. As of 2026, expect roughly: a one-time brand registration fee of $4 (up to $44 for Standard brands with secondary vetting), a one-time $15 campaign vetting fee, and a recurring campaign fee of about $2–$10 per month depending on use case. Registered traffic also carries small carrier surcharges per message segment. Full breakdown in our 2026 cost guide.

How long it takes

Brand registration usually resolves in 1–5 business days. Campaign approval takes anywhere from a few days to four weeks, with the industry average around two weeks for standard use cases. The single biggest factor is whether your submission passes review the first time; a rejection can restart the clock. Timelines and acceleration tips in our approval timeline guide.

What carriers check, and why websites matter

Most businesses are surprised to learn that campaign reviewers open your website. They check that:

• Your privacy policy explicitly addresses SMS data, and in particular that opt-in data is not shared with third parties for marketing. This is the #1 rejection cause. See privacy policy requirements.
• Your opt-in flow is visible and compliant: a clear disclosure where phone numbers are collected. See opt-in consent requirements.
• Your business details (legal name, EIN, website) match what you registered.
• Your sample messages match your stated use case and identify your brand.

Because the review is largely a website audit, you can predict the outcome before you submit. That is exactly what our free scanner does: it reads your site the way a reviewer would and flags what will fail. Run it before you register and fix issues on your terms, not after a two-week review cycle. And when a campaign does get rejected, here is how to fix every common rejection reason.

The bottom line

A2P 10DLC is not optional, and it is not going away. Carrier enforcement has only tightened since full blocking began in February 2025. But it is also not mysterious: register your brand accurately, describe your campaign honestly, make sure your website backs up your story, and approval is routine.

Frequently asked questions

Do I need A2P 10DLC registration if I only send a few messages a day?

Yes. There is no volume exemption: carriers block unregistered A2P traffic regardless of volume. Low-volume senders can use the cheaper Low Volume Standard or Sole Proprietor registration types, but registration itself is mandatory.

Does A2P 10DLC apply to Canada or other countries?

A2P 10DLC is a US carrier framework and applies to messages terminating on US networks. Canada has its own long code rules, and other countries have separate sender registration regimes. If you text US numbers, you need 10DLC registration no matter where your business is located.

What happens if I send without registering?

Since February 1, 2025, US carriers and major providers like Twilio block 100% of unregistered 10DLC traffic. Messages fail with errors such as Twilio error 30034 and never reach the handset.

Is 10DLC the same as a short code?

No. A short code is a 5–6 digit number with very high throughput and a separate (more expensive) approval process. 10DLC uses standard local 10-digit numbers with moderate throughput at much lower cost.