A2P 10DLC explained: registration in plain English

A2P 10DLC is the US system for registering businesses that send text messages from ordinary 10 digit phone numbers. A2P stands for application to person (software sending texts to people), and 10DLC stands for 10 digit long code, meaning a standard local number. Before you text customers this way, you register your business (the brand) and what you will send (the campaign) through your messaging provider. Carriers block or filter traffic that is unregistered or does not match its registration.

This is a general explainer, not legal or compliance advice. Carrier requirements and provider processes change over time, so follow what your provider asks for.

Why it exists

Ordinary local numbers were built for people texting people. As businesses started sending reminders, alerts and marketing from those same numbers, the US carriers needed to know who was sending what, so they could let legitimate business texts through and stop spam. Registration ties every business texting program to a verified sender and a described purpose.

For you, the practical effect is that you cannot buy a number and start texting your list the same afternoon. There is paperwork first, and the quality of that paperwork affects how your texts are delivered.

The two parts: brand and campaign

Brand registration

The brand is your business. You submit details such as:

• Your legal business name, exactly as registered.
• Your tax ID (an EIN for US businesses).
• Business type and address.
• Your website.
• A contact person.

These are checked against public records. Mismatches, such as a trade name entered in place of the legal name, or a tax ID that does not match the name, are a common cause of delays.

Sole proprietors without an EIN usually have a separate, lighter registration path that comes with tighter limits, such as a single campaign and a single phone number.

Campaign registration

The campaign describes what you will send and how people agreed to receive it. Expect to provide:

• The use case, such as customer care, account notifications or marketing.
• A description of the messages.
• Sample messages that look like what you will really send.
• How people opt in, and where a reviewer can see it, such as the web address of your form.
• Your opt out and help keywords (STOP and HELP) and the replies people get.
• Whether your messages contain links or phone numbers.

Campaigns are reviewed before approval. When one is rejected, the cause is often fixable in an afternoon: the opt in is not visible on the website, the samples do not match the use case, the samples leave out the business name, or the privacy policy does not say how mobile numbers are handled.

Once a campaign is approved, your phone numbers are assigned to it.

What carriers look at after approval

Approval does not guarantee every message arrives. Carriers keep filtering on content and behavior, and these cause trouble:

• Messages that do not match the registered campaign, such as registering for appointment reminders and then sending promotions.
• Shared public link shorteners. Use links on your own domain instead.
• Messages without a business name, so the person cannot tell who is texting.
• High opt out rates or spam reports after a send.
• Texts to people who never opted in, including old or purchased lists.
• Restricted content. Some categories face extra rules or are not allowed on standard campaigns.

How many messages you can send, and how fast, also depends on your brand's verification and your campaign type. A sudden large send from a new registration is more likely to run into those limits.

Terms you will see in your provider's dashboard

• The Campaign Registry (TCR): the central registry that holds brand and campaign registrations for the US carriers. Your provider submits to it on your behalf.
• Brand: the verified business sending the messages.
• Campaign: a registered use case with its description, sample messages and opt in details.
• Vetting: an extra check of your brand, offered by some providers, that can raise your sending limits.
• Throughput: how many messages you can send in a given period.
• Opt in, opt out and help messages: the replies people get when they subscribe, reply STOP or reply HELP.

If a term in your dashboard does not match these, ask your provider's support team. They see rejections every day and can usually tell you what a reviewer wanted.

Fees and timing

Registration involves fees from the registry and the carriers, which providers usually pass through along with their own charges. Your provider can tell you the current amounts.

Approval can take anywhere from a few days to a few weeks, and a rejection sends part of it back to the start. Begin before you plan to launch a campaign, not the week of it.

Other kinds of numbers

• Toll free numbers can also send texts in the US, and they go through their own verification process.
• Short codes (5 or 6 digit numbers) are built for very high volume, and take longer and cost more to get.

For most coaches, consultants, creators and agencies texting their own leads and clients, a registered 10DLC number is the usual choice.

Getting approved: a step list

1. Put your opt in on a public page: a form with a phone field, an unchecked consent box and a disclosure naming your business, the types of messages, that frequency varies, that message and data rates may apply, and how STOP and HELP work.
2. Make sure your website shows your business name, a way to contact you, terms and a privacy policy. Many providers expect the privacy policy to say you do not share or sell mobile numbers or opt in data to third parties for their marketing.
3. Gather your legal name, EIN and address exactly as they appear on your tax records.
4. Register the brand through your messaging provider.
5. Pick the campaign use case that matches what you will really send. If you plan to send reminders and promotions, say so.
6. Write a few sample messages that include your business name, and opt out instructions where they belong.
7. Set up your STOP and HELP replies.
8. Submit, wait for review, fix anything flagged and resubmit.
9. Assign your numbers to the approved campaign.
10. Keep sending what you registered. If your texting program changes, update the campaign.

When messages that used to arrive stop arriving

Work through these in order. Did the content drift from what you registered? Did you start using a public link shortener? Did opt outs jump after a recent send? Did you start texting a list that never opted in? Is the number still assigned to an active campaign? Your provider's delivery logs usually show carrier error codes that point at the cause, and their support team can read them with you.

How Niche fits with 10DLC

Niche Engine sends and receives texts through Twilio, and each client runs on their own Twilio account and phone numbers, so your registration and your sender reputation stay yours. We help you connect them during setup. The habits carriers reward are part of how Niche texts: it texts only people who agreed on one of your forms, never imported spreadsheets, honors STOP at once and holds marketing texts overnight in each person's time zone. See AI texting and contacts, or book a call to talk through setup.