A2P 10DLC: How to Text Customers From a Business Number Legally

A2P 10DLC registration is how US carriers let a business text customers from a regular 10-digit number. You register your business (the brand) and what you'll send (the campaign) with The Campaign Registry through your texting provider, and the registry's 2026 overview says every business texting on 10DLC must do it, even for one-to-one messages that aren't marketing (The Campaign Registry, 2026). Unregistered texts have been blocked since February 3, 2025 (RingCentral, 2025).

What is A2P 10DLC, and who has to register?

A2P means application-to-person: texts a business sends from software, not from someone's personal phone. 10DLC means 10-digit long code, which The Campaign Registry calls the sanctioned standard for business texting from a traditional 10-digit number. Its 2026 overview says any business using 10DLC to text customers or employees must register, including businesses sending individual, non-marketing messages (The Campaign Registry, 2026).

Registration has two parts. The brand is your business: legal name, EIN, address, and contact details (The Campaign Registry, 2026). The campaign is your use case, such as Marketing for promotions or Customer Care for two-way support (The Campaign Registry, 2026). Carriers asked for this so they can see who is sending messages and what is being sent (The Campaign Registry, 2026). You don't file with the registry yourself. It tells businesses to register through their messaging provider, and it doesn't approve campaigns; your provider and its carrier connection partners do (The Campaign Registry, 2026).

What happens to texts from an unregistered number?

They don't arrive. RingCentral told customers that on February 3, 2025, aggregators operating on behalf of US mobile carriers began enforcing the blocking of unregistered outbound SMS traffic (RingCentral, 2025). Providers enforce it too: Twilio's current error documentation says it blocks messages to US numbers sent from a 10DLC number that isn't tied to an approved campaign (Twilio, 2023).

The real cost is the appointment that falls through. A 2026 meta-analysis of 10 trials found that people who got appointment reminders were on average 11% more likely to attend than people who got none (Journal of Hospital Management and Health Policy, 2026). The trials come from hospital clinics, so read it as direction, not a forecast. More fixes are in our guide to appointment no-shows.

Worked example: Assumptions: you send 200 appointment confirmation texts a month from an unregistered number, so all of them are blocked; 85 of every 100 customers would show up without a reminder; and an average appointment is worth $150. The 2026 meta-analysis found reminders made people 11% more likely to attend (risk ratio 1.11) (Journal of Hospital Management and Health Policy, 2026). Without reminders: 200 × 0.85 = 170 kept appointments. With them: 170 × 1.11 = 188.7. The gap is 18.7, about 19 more missed appointments a month. At $150 each: 18.7 × $150 = $2,805 a month. Compare the registry's own charge for a standard campaign: $4.50 once for the brand plus $10 a month with a 3-month minimum, or $4.50 + $30 = $34.50 for the first quarter (The Campaign Registry, 2026). This is an illustration, not a forecast.

Once your texts are getting through, the SMS ROI calculator shows what a registered, opted-in list can earn per send.

What does a 10DLC campaign registration need?

A campaign registration spells out what you'll send and how people agreed to get it. The Campaign Registry's July 2026 user guide lists a campaign description, a call-to-action or message flow showing how consumers opt in, at least 1 sample message (2 for marketing, mixed, sole proprietor, and several other campaign types), and STOP and HELP keywords with the replies you'll send (The Campaign Registry, 2026).

• Use case. Pick the campaign type that matches what you actually send (The Campaign Registry, 2026). Appointment reminders and promotions are different jobs.
• Message flow. Describe every way a customer opts in: website form, booking page, text-in keyword, or front desk. If you use more than one method, you must list them all (The Campaign Registry, 2026).
• Sample messages. Real examples with your business name that match the use case.
• Opt-out and help. STOP and HELP are mandatory keywords, each with a reply message (The Campaign Registry, 2026).
• Privacy policy and terms. The link fields are optional in the registry, but a compliant privacy policy and compliant terms and conditions are both required (The Campaign Registry, 2026). Nirvani's own SMS privacy policy shows one layout.

Your opt-in wording should follow CTIA's Messaging Principles and Best Practices (May 2023): name the program, the number that will text them, and your business, and state any fees and how to opt out (CTIA, 2023). An example for a booking form: "Get appointment confirmations and reminders by text from [Business Name] at [your texting number]. Msg frequency varies. Msg and data rates may apply. Reply STOP to opt out, HELP for help. See our SMS privacy policy."

How much does 10DLC registration cost, and how long does it take?

The Campaign Registry's July 2026 price list, current when we checked in October 2026, shows $4.50 per brand submission ($4.00 for a sole proprietor) and monthly campaign fees of $1.50 for low volume, $2 for sole proprietors, and $10 for most other campaigns, billed for at least 3 months (The Campaign Registry, 2026). Resubmitting a brand that fails verification costs the brand fee again (The Campaign Registry, 2026). Those are the registry's charges to providers. Ask yours what it adds.

Timing varies. The registry says campaign review times can range from 1 to 4 weeks (The Campaign Registry, 2026). Brand verification fails most often because the legal company name and EIN don't match what's filed with the federal government (The Campaign Registry, 2026), so copy both straight from your IRS EIN confirmation letter.

No EIN? The sole proprietor route

The sole proprietor option is for small businesses and individuals in the US and Canada without an EIN. It's capped at one campaign and one phone number, with limits of 1,000 messages a day on T-Mobile and 15 a minute on AT&T (The Campaign Registry, 2026). Only pre-approved providers can offer it (The Campaign Registry, 2026), so check before you pick one.

Does 10DLC registration make my texts legal?

No. Registration gets your texts through the carriers, but consent law still applies. CTIA's 2023 guidelines expect senders to follow the TCPA and FCC rules, get consent before texting, and get express written consent for marketing texts (CTIA, 2023). FCC rules say a reply such as stop, quit, end, cancel, or unsubscribe revokes consent, and opt-outs must be honored within ten business days (Electronic Code of Federal Regulations, 2024).

Keep proof. CTIA asks senders to record each opt-in's timestamp, how it was collected, the wording shown, the campaign, and the phone number, and to send one final confirmation after an opt-out and nothing more (CTIA, 2023). If you're adding AI to calls or texts, read how the TCPA applies to AI voice calls before you launch. This is general information, not legal advice.

What to do this week

1. Check your status. Log in to your texting provider and find the 10DLC or A2P registration page for your brand, campaign, and number. On Twilio, a blocked unregistered text returns error 30034 (Twilio, 2023).
2. Gather your brand details. Pull your IRS EIN confirmation letter and copy your legal name, EIN, and address exactly (The Campaign Registry, 2026). Add your website; the registry strongly recommends it (The Campaign Registry, 2026).
3. Write your opt-in language and add it to every form, booking page, and sign-up sheet that collects phone numbers.
4. Publish an SMS privacy policy and terms on your site, then write two sample messages plus your STOP and HELP replies.
5. Start an opt-in log with date, time, source, wording shown, and phone number for every new contact (CTIA, 2023).

Where Nirvani fits

Nirvani captures incoming calls, texts, social messages, and website chat in one system. Its AI employees answer, qualify leads, book appointments into your calendar, follow up on no-shows, handle basic scheduling, and send review requests. It runs 24/7, in your business's voice, around the processes your team already uses. N1 is the entry operating system.