> For the complete documentation index, see [llms.txt](https://docs.limecall.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.limecall.com/virtual-numbers/us-carrier-registration.md).

# US carrier registration (10DLC)

What you must register before texting US numbers, and how.

Open **Settings → Messaging**, or **Settings → US carrier registration**.

## What it is

10DLC — ten-digit long code — is the US scheme for businesses sending application-to-person text messages from ordinary local numbers.

US carriers require every business to register its identity and its messaging campaigns before messages are delivered. Unregistered traffic is filtered or blocked outright.

{% hint style="warning" %}
This is enforced by US carriers, not by LimeCall. No provider can send unregistered A2P traffic to US numbers reliably, and no setting in LimeCall bypasses it.
{% endhint %}

## Who needs it

Anyone sending text messages to US phone numbers from a US local number, including:

* appointment reminders and confirmations,
* notifications and alerts,
* AI receptionist text replies,
* marketing messages.

It applies to transactional messages as well as marketing.

You do not need it if you never text US numbers.

## The two stages

**Brand registration.** Your business identity — legal name, EIN or equivalent tax ID, address, website, and a contact. The details must match your official registration exactly; a mismatch against tax records is the most common failure.

**Campaign registration.** What you will actually send. You describe the use case, provide sample messages, and show how people opt in and opt out.

## Getting the campaign approved

Reviewers check specific things:

* **Sample messages** must be realistic and include your business name.
* **Opt-in** must be described accurately and demonstrably — where on your site people consent, and what the wording says. If you claim web opt-in, the reviewer may look at the page.
* **Opt-out** instructions must be present.
* **Use case** must match what you actually send. Registering as transactional and sending marketing gets the campaign revoked.

## How long it takes

Brand registration is often same-day to a few days. Campaign approval typically takes a few business days, longer if anything needs clarifying.

Start well before you need it.

## Throughput

Approved campaigns get a throughput allowance based on your brand's trust score. Higher trust means more messages per minute.

Trust improves with a verified EIN, a real website and a clean sending history.

## Toll-free is different

Toll-free numbers use a separate toll-free verification process, not 10DLC. If you are only using a toll-free number, do that instead. See [Addresses & verification](/virtual-numbers/address-and-verification.md).

## What happens without it

Messages are accepted by the system and then filtered by carriers. You see them as sent; recipients never receive them. There is often no error, which is why unregistered accounts can appear to be working for some time before anyone notices.

If your delivery rates look wrong, check registration status before anything else.

## Outside the US

10DLC is US-specific. Other countries have their own rules — the UK and much of Europe use alphanumeric sender IDs with their own registration, and some countries require pre-registered templates. Check the requirements for each country you message.