Text Clients from Your Business Number using Twilio: Number, A2P 10DLC and a First Test Text

Updated October 14, 2026. Built against the tool’s current screens and checked step by step. How we check this lesson

Small offices lose work in quiet ways. A new caller hangs up without leaving a voicemail and calls the next firm. Clients never open the document reminder email. And when a staff member texts clients from a personal phone, those conversations leave with that person. Texting from one office number fixes all three, because clients read texts and can text back. This free lesson starts with the business case, then sets up Twilio step by step in a practice copy of the Twilio Console: buy a local number, register it for business texting (A2P 10DLC), check that it is cleared to send, get a test text ready for when it is approved, and find the Account SID and Auth Token that other apps need. No account is needed to practice, and nothing is bought or sent.

Start here first: Your First Voice Agent in ElevenLabs: An After-Hours Receptionist (module 1 of AI Voice Agents)

In the course: Part 11 · AI Voice Agents (Module 76 of the full course)

The business case: what unread reminders and missed calls cost

Take a six-person accounting office. Last week only five of twelve clients opened the "documents due Friday" email, two booked clients missed their appointments, and a new caller hung up and called another firm. If each empty appointment slot is about $150 of billable time, two a week is about $1,200 a month. Those are example numbers, so work out your own: missed appointments a month, times what an hour of your time bills, plus the new clients who never called back.

The third cost is harder to see. When staff text clients from their own phones, the client's history sits on someone's personal phone, nobody else can follow up, and it leaves when they do.

What changes after you set it up

• The office has one local number that sends and receives texts, so reminders and document requests arrive where clients actually look.
• Clients can text back, and every reply comes to the office number, not to a personal phone.
• The number is registered with US carriers (A2P 10DLC), so your texts are delivered instead of filtered.
• You know where the Account SID and Auth Token live, so tools like n8n can send texts for you later.

The example: Oakline Tax & Accounting

Oakline Tax & Accounting is a made-up firm in Harrisburg, Pennsylvania. Maya runs the front desk. She buys a local 717 number, registers the firm as a Low Volume Standard brand, describes a Low Volume Mixed campaign (appointment reminders, document requests and replies to client questions, to clients who opted in on the intake form), and texts her own phone a test once the campaign is approved.

Who this is for

Office managers, owners and front-desk staff at small professional offices: accounting and bookkeeping firms, law offices, agencies and clinics. No coding is needed. You need a Twilio account to do it for real, and to register for US texting the account must be upgraded (paid). It is the setup lesson before the [missed-call text-back lesson](lesson:voice-agents-missed-call-text-back), which uses this number to text callers back automatically.

A2P 10DLC in plain words

US mobile carriers only deliver business texts from ordinary 10-digit numbers ("10DLC") when the business and its reason for texting are registered. That registration is called A2P 10DLC (application-to-person). Without it, texts fail with error 30034, "Message from an Unregistered Number", and show as Undelivered in your logs.

It has four parts in the Console checklist. The compliance profile is your business on paper and must match your IRS records exactly. The messaging service holds your number for texting. The brand tells carriers who is texting: Sole Proprietor (no EIN), Low Volume Standard (an EIN and under 6,000 text segments a day, right for most small offices) or Standard. The campaign says what you will text and how people agreed to it.

How to get the campaign approved the first time

• Campaign description: say who you are, who you text and what about, for example "texts existing clients who opted in on our intake form: appointment reminders, requests for missing tax documents, and replies to their questions. No marketing." A vague line like "respond to messages as an agent" is a common rejection (error 30886).
• How end users opt in: name the exact place (an intake form at a public web address, a signed paper form, a client texting you first), quote the checkbox wording, and link your privacy policy. An opt-in reviewers cannot check is the top rejection reason (error 30909).
• Sample messages: real examples that start with your business name and end with "Reply STOP to opt out".
• Twilio answers STOP and HELP for you by default, so you do not have to build that.

Timelines and fees (checked October 2026)

A local number is $1.15 a month. Registering a Low Volume Standard or Sole Proprietor brand is $4.50 once; a Standard brand is about $46 once because it includes secondary vetting. Every campaign has a $15 one-time review fee, then a monthly fee: $1.50 for Low Volume Mixed, $2 for Sole Proprietor and $10 for Standard use cases. Each text is under a cent plus a small carrier fee.

A new compliance profile can take up to 72 hours. A low-volume brand is often approved in minutes, but a manual review can take seven business days or more. Campaign reviews are currently taking about 10 to 15 days and sometimes two to three weeks, so start early. Fees and timelines change, so check Twilio's pricing and help pages before you register.

What this saves you

Reminders that get read, so fewer empty appointment slots and fewer late documents. One office number for every client conversation, so nothing lives on a personal phone. And a registered number that other tools can use. For about $1.15 a month for the number, $1.50 a month for the campaign and $19.50 once, a small office gets a channel clients actually read. Next business case: [text back every missed client call in seconds](lesson:voice-agents-missed-call-text-back) with Twilio and n8n.

Step by step: Text Clients from Your Business Number using Twilio: Number, A2P 10DLC and a First Test Text

All 43 steps of the interactive module, in order. In the module you watch each one, then do it yourself in a practice copy that checks your work.

1. Why clients need a text from you

1. See what slipped last week. Maya runs the front desk at Oakline Tax & Accounting, a six-person firm. Last week a new caller hung up without leaving a voicemail, most clients ignored the document reminder email, and a staff member texted a client from his own phone. Click the row where the email reminder went to 12 clients.

   Maya runs the front desk at Oakline Tax and Accounting. It's a six person firm. Look at last week. A new caller hung up, and called another firm. Only five of twelve clients opened the document reminder. And Jordan texted a client from his own cell phone.

2. Put a price on it. Say two booked clients a week miss their appointment and each empty slot costs about $150 of billable time. That is about $1,200 a month. Example numbers, so use your own. Click the total.

   Now put a price on it. Say two clients a week miss their appointment. Each empty slot is about a hundred fifty dollars of billable time. That's about twelve hundred dollars a month. These are example numbers, so use your own.

3. Meet Twilio. Clients read texts, and they can text back. Twilio gives your office its own phone number that can send and receive texts, so nobody uses a personal cell. Click the Twilio card to open the Console.

   Clients read texts. And they can text you back. Twilio gives the office its own phone number, that sends and receives texts. So nobody uses a personal cell phone.

2. Find your way around the Console

4. Open Communications. This is the Twilio Console home. Your account card shows the Account SID and a hidden Auth Token. We will come back to those. Texts and calls live under Communications in the left menu. Click it.

   This is the Twilio Console. Your account card shows the Account S I D, and a hidden Auth Token. We'll come back to those at the end. Everything for texts and calls is under Communications, in the left menu.

5. Open Numbers & senders. Click Numbers & senders.

   Your phone numbers live under Numbers and senders.

6. Open the overview. Click Overview.

3. Choose your business number

7. Set up a new number. This is Numbers & Senders. My Inventory is empty because the firm has no Twilio number yet. Click Set up a new phone number.

   This is Numbers and Senders. My Inventory is empty. The firm doesn't have a Twilio number yet.

8. Ask for texting. The destination country is already United States. Under What capabilities do you want this number to have?, tick SMS.

   Your clients are in the United States, and that is already picked. Now say what the number must do. Tick S M S. That means it can text.

9. Open Number type. Click the Number type box.

   Next, the type of number.

10. Choose Local. Pick Local. A local area code looks familiar to clients, so they pick up and reply. (Toll-free numbers need their own, separate registration.)

    Pick Local. A local area code looks familiar, so clients are more likely to reply. Toll free numbers have their own, separate registration.

11. Search your area code. In Search by digits or phrases, type your area code: 717. Match To stays on First part of number.

    Now search for your own area code. Match To stays on, first part of number.

12. Search. Click Search.
13. Pick a number. Every result can do Voice, SMS and MMS and costs $1.15 a month. Choose +17175550142 with the round button on the right.

    Every number in the list can call, text, and send pictures. Each one is a dollar fifteen a month. Pick the first one, with the round button on the right.

14. Review it. Click Next. On the real Review number page you check the number and the monthly fee, then buy it. In this practice copy nothing is bought.

    On the review page, you check the number and the price, then you buy it. In this practice copy, nothing is bought.

15. Buy the number. Check (717) 555-0142 and $1.15 monthly, then click Buy. Twilio charges your account balance.

    Check the number, and the monthly fee. Twilio takes it from your account balance.

4. Register to text (A2P 10DLC)

16. Open the compliance profile. The number is yours, but SMS says Registration required. US carriers block texts from unregistered business numbers. This checklist is the registration, called A2P 10DLC. Open Select or set up compliance profile.

    The number is yours. But look. S M S says, registration required. In the US, phone carriers block texts from business numbers that aren't registered. This checklist is that registration. It's called A two P, ten D L C.

17. Use the business profile. A compliance profile is your business on paper: legal name, EIN, address, website and a person who can answer for it. They must match your IRS records exactly. Select the Oakline profile.

    A compliance profile is your business on paper. The legal name, the E I N, the address, the website, and a person who can answer for it. They must match your I R S records exactly.

18. Select a messaging service. A messaging service is a container that holds your number for texting. Click Select messaging service.

    Next, a messaging service. Think of it as a folder that holds your texting numbers.

19. Create one. This opens Select or create a messaging service. You have none yet, so open Messaging service friendly name and pick Create New Messaging Service under New. On the real page you then click Complete.

    You don't have one yet. Twilio puts your number in it.

20. Start the brand registration. Now the brand. It tells carriers who is texting. Click Set up A2P Brand registration. It opens A2P Brand Registration: first Basic information, where you name it and use your compliance profile, then Registration details.

    Now the brand. That tells carriers who is texting. You name it, use the compliance profile you just picked, and click Next.

21. Pick the brand type. A small office with an EIN and fewer than 6,000 texts a day is Low Volume Standard: $4.50, one time. Pick it and finish the form. A low-volume brand is often approved in minutes, but a manual review can take 7 business days or more.

    A small office, with an E I N, sending fewer than six thousand texts a day, is Low Volume Standard. It's four dollars fifty, one time. Pick it, and finish the form. It's often approved in minutes. A manual review can take a week or more.

22. Open the use case. The campaign says what you will text and why people agreed to it. This is where most registrations get rejected. Click the Use case box.

    Last, the campaign. It says what you'll text, and how clients agreed to it. This is where most registrations get rejected. So take your time.

23. Choose Low Volume Mixed. Choose Low Volume Mixed: reminders, document requests and replies, at low volume. It costs $1.50 a month.

    It covers reminders, document requests, and replies, at low volume. It's a dollar fifty a month.

24. Describe the campaign. In Campaign description, say who you are, who you text and what about. Vague text like "respond to messages as an agent" gets rejected. Paste the description.

    Now the Campaign description. Say who you are, who you text, and what about. Be specific. A vague line like, respond to messages as an agent, gets rejected.

    Oakline Tax & Accounting texts existing clients who opted in on our intake form: appointment reminders, requests for missing tax documents, and replies to questions they send us. No marketing.

25. Explain how clients opt in. In How do end-users opt in to receive messages?, say exactly where clients agree, the words they see, and where your privacy policy is. A missing or unclear opt-in (error 30909) is the top reason campaigns are rejected. Paste it.

    This box is the big one. How do clients opt in? Say exactly where they agree, the words they see, and where your privacy policy is. If reviewers can't check it, the campaign is rejected.

    Clients opt in on our client intake form at oaklinetax.com/intake by checking an unchecked box: "Yes, text me about my appointments and documents. Msg & data rates may apply. Msg frequency varies. Reply STOP to opt out, HELP for help." Our privacy policy is at oaklinetax.com/privacy.

26. Add a sample message. In Sample message #1, paste a real example. Start with your business name and end with how to opt out.

    Add a sample message. A real example. Start with the business name, and end with, reply STOP to opt out.

27. Add a second sample. Paste Sample message #2, a document request.

    And a second one. A document request.

28. Confirm and submit. Tick I confirm the information entered here is ready to submit for review. On the real page you then click Complete. Twilio charges a $15 one-time review fee. Reviews are taking about 10 to 15 days, sometimes longer. You can not text clients until it is approved.

    Tick the box that says the information is ready to submit for review. There's a fifteen dollar review fee, one time. Reviews take about ten to fifteen days, sometimes longer. Until it's approved, the number can't text clients. So start this early.

5. Check the number can text

29. Jump ahead two weeks. Two weeks later, Twilio emails Maya: the campaign is approved. Click View all my numbers to check.

    Let's jump ahead. Two weeks later, Twilio emails Maya. The campaign is approved.

30. Read the traffic status. Look at Traffic Status for your number. Messaging enabled means it can text. If it says Messaging disabled with Complete A2P registration under it, it can not text yet. Click Messaging enabled.

    Look at Traffic Status. Messaging enabled, means the number can text. If it says, Messaging disabled, with complete A two P registration under it, it can't text yet.

6. Get your first test text ready

31. Open Messaging. Now get a test text ready. In the left menu, click Messaging.
32. Open the overview. Click Overview under Messaging.
33. Try out SMS. Top right: Send an SMS to yourself to see how Messaging works. Click Try out SMS.

    At the top right, Twilio offers to send a text to yourself.

34. Text yourself. In To, type your own mobile number. Here: +15550100199. Only text people who agreed to it, and for a test, that is you.

    In the To box, type your own cell phone number. For a test, only ever text yourself.

35. Pick your number. Click From and choose +17175550142. With a registered number there is no Action required to proceed note under it.

    Because it's registered, there's no action required note under it. If you see that note, the registration isn't finished.

36. Write the message. In Message, type Oakline Tax: test text from our office number.

    In the message box, type, Oakline Tax, test text from our office number.

37. Send it once you are approved. Do not send yet. Wait until Twilio emails that the campaign is approved and Traffic Status says Messaging enabled. Then click Send SMS once, to your own phone. Before approval the text is blocked. Click the note.

    Don't send it yet. Wait for the email that says your campaign is approved, and for Traffic Status to say, messaging enabled. Before that, the text gets blocked.

38. Check the log. Click Logs. Your test shows up here after you send it. Delivered means it reached the phone. Undelivered with Error 30034 means the number is not registered yet.

    Your test shows up here, after you send it. Delivered, means it reached the phone. If you see Undelivered, with error three zero zero three four, the number isn't registered yet.

7. Where your keys live

39. Go home. That is the setup done. Click Home in the left menu.

    That is the setup done.

40. Open API keys & auth tokens. Other apps, like n8n, connect to Twilio with your Account SID and Auth Token. Under the account card, click API keys & auth tokens.

    Other apps, like N eight N, connect to Twilio with your Account S I D and Auth Token. Under the account card, click, API keys and auth tokens.

41. See where the token lives. Click the Auth tokens tab. Your Account SID is here, and the Primary auth token stays hidden behind the eye icon. Treat it like a password: never paste it in an email or a chat. Twilio recommends an API key for each app instead.

    Here is your Account S I D. And the primary auth token, hidden behind the eye icon. Treat it like a password. Never paste it in an email or a chat. Twilio suggests a separate API key for each app instead.

8. What this saves you

42. See what changed. Click Done.
43. What this saves you. The firm now texts from one registered office number. Reminders get read, clients can reply, and nobody texts from a personal phone. Click the card.

    Here's what changed. The firm texts from one registered office number. Reminders get read. Clients can text back. And nobody uses a personal phone. Next, use this number to text back every missed call, automatically.

Frequently asked questions

Why can't my Twilio number send texts?

In the US, a 10-digit business number must be registered for A2P 10DLC before carriers deliver its texts. In Numbers & Senders, Traffic Status shows Messaging disabled with Complete A2P registration until the brand and campaign are approved. Texts sent before then fail with error 30034.

What is A2P 10DLC?

It is the US registration for businesses that text from ordinary 10-digit numbers. You register your business (the brand) and what you text and how people opted in (the campaign). Approved numbers get delivered instead of filtered.

How long does A2P 10DLC approval take?

A low-volume brand is often approved in minutes, but manual reviews can take a week or more. Campaign reviews are currently taking about 10 to 15 days, sometimes two to three weeks.

How much does it cost to text clients with Twilio?

A local number is $1.15 a month. Registration is $4.50 for a low-volume brand and $15 for the campaign review, once, then $1.50 a month for a Low Volume Mixed campaign. Each text costs under a cent plus a small carrier fee. Check Twilio's pricing page for current numbers.

Why was my A2P campaign rejected?

The most common reasons are an opt-in reviewers cannot verify (error 30909) and a vague campaign description (error 30886). Say exactly where clients agree to texts, quote the wording they see, link your privacy policy, and describe who you text and about what.

Where do I find my Twilio Account SID and Auth Token?

On the Console home, on your account card, and under API keys & auth tokens. The Auth Token is hidden behind an eye icon. Treat it like a password, and prefer a separate API key for each app.

Is this lesson free?

Yes. Stepthrough is completely free and the practice copy needs no Twilio account.

Start this module free

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