SMS Registration: The Complete Guide For Text Message Marketing

SMS marketing is powerful. But it also comes with plenty of regulations that marketers need to follow.

You probably know by now that sending business texts in the U.S. requires some kind of registration: A2P 10DLC, or other carrier / campaign‐registration rules.

What many marketers don’t grasp is just how much that registration, and the components around it, affect whether your message is delivered, filtered, or blocked—and how tiny mistakes in the registration process can tank deliverability.

The Meera team has years of experience helping companies register their brands so they can send text messages successfully. In this article, we’ll dig into:

• What A2P 10DLC really is, under the hood
• The components of “brand + campaign + phone number + trust score” and why each matters
• What happens when registration is missing or flawed—filtering, higher fees, full block
• Technical registration steps + common gotchas
• How a platform like Meera could simplify all this for you
  
  

What Is A2P 10DLC: A Technical Breakdown

A2P stands for Application-to-Person: messages sent from an application/software (e.g., CRM, marketing tool) to a person’s phone. It’s different from P2P (person to person).

10DLC means you’re using a standard 10-digit long code phone number (local format) rather than a short code or toll-free number. Originally, long codes were intended for personal / P2P use; carriers introduced 10DLC to officially allow business (A2P) traffic over long codes while establishing rules & oversight.

Carriers and regulatory bodies (e.g., The Campaign Registry, TCR; CTIA; telecom carriers themselves) require registration of brands and campaigns so they can vet:

• Who is sending (brand identity, legal existence)
• What is being sent (campaign use case, opt-in mechanism, content)
• How sending complies with industry rules (TCPA, privacy, opt-out, etc.)

Once registered and approved, you get a trust score or some kind of classification which dictates both how fast, how often, and how reliably messages are passed through carrier networks. 

Why Many Marketers Underestimate the Filtering & Delivery Risk

Since registration has become mandatory (or close to it) for US SMS campaigns via 10DLC, a number of things happen that are not always obvious:

1. Heavier Filtering
   Messages from unregistered or improperly registered 10DLC traffic are more aggressively filtered by carriers. Even if they aren’t fully blocked, they may be delayed, dropped, or sent to secondary/spam channels.
   
   
2. Higher Fees / Pass-Through Costs
   Unregistered traffic often incurs higher pass-through carrier fees. Carriers have explicitly raised the cost of sending unregistered SMS/MMS via local long codes.
   
   
3. Throughput Limits & Trust Score Throttling
   Even after registration, your throughput (how many messages you can send, how fast) depends on the campaign type, your brand, how clean your opt-in records are, etc. Unregistered or low-trust campaigns are limited.
   
   
4. Risk of Complete Blocks
   In many cases carriers are moving toward fully rejecting unregistered 10DLC traffic. As of certain deadlines, if traffic is unregistered, it may simply be dropped.
   
   
5. Registration Delays / Rejections Due to Minor Errors
   Because of the vetting required, even small misalignments in business info, website, sample messages, or opt-in documentation can lead to rejections, which means your campaign is functionally dead until those are fixed.
   
   

So the core “problem” isn’t that marketers don’t know registration is required—it’s that many don’t understand how deeply missing or flawed registration feeds into filtering / deliverability problems, and how many moving parts there are.

What Exactly Registration Involves: Brand, Campaign, Phone Number, Use Case & Trust Score

Here are the technical parts of registration, and what carriers / TCR require. Each of these must be done correctly for your campaign to avoid filtering:

What Happens When Registration is Missing or Incorrect

Even “mostly done” registration can leave you vulnerable. Here are scenarios and consequences:

• Messages are heavily filtered: Carriers apply spam filters more aggressively to unregistered traffic. They may silently drop messages, i.e. the user never sees them and you may get fewer delivery receipts.
• Opt-out / compliance failings lead to rejections: If your campaign description doesn’t clearly show how people opted in, or if sample messages are misleading, the campaign may be rejected or approved with restrictions.
• Inconsistent data → delay: If your legal address, EIN, business name, or website don’t match official records, registration may stall, be rejected, or require resubmission.
• Throughput caps: Without good registration and a good trust score, carriers limit how many messages you can send in given time windows; big sends get throttled.
• Cost penalties: Unregistered messages often incur higher per-message fees, or carriers pass through higher fees. Over large volume, that cost adds up.
  
• Eventual full blocking: At some point (or already, depending on carrier / region), carriers may refuse all unregistered 10DLC messages entirely. Your campaign might “send” but never arrive.
  
  

Checking Registration Status & Common Gotchas

Understanding the process is one thing; actually executing it is where people often hit pitfalls. Here are common gotchas and how to avoid them:

1. Delay from vetting
   Brand registration may take several business days (2-3 days often, but more if any verification docs are missing). Campaign registration after that also takes time.
   
   
2. Mismatch in public vs registration records
   If your business name / address / phone number doesn’t match publicly available business registries or your website, or your domain registration, that raises flags. Have consistent info.
   
   
3. Sample message content problems
   Sample messages you submit in the campaign registration must reflect what you’ll send — content, frequency, opt-out, identity. If they don’t, campaign can be rejected or approved with low throughput.
   
   
4. Incomplete opt-in documentation / vague methods
   You need to show proof or description of how people consented (checkboxes, signup forms, etc.), how opt-out works (“Reply STOP”, etc.), any privacy policy, etc.
   
   
5. Changing use case without updating registration
   If you originally registered for “transactional SMS” but later start sending marketing/promotional messages, that’s a mismatch. Either register a new campaign, or update the existing one accordingly.
   
   
6. Multiple numbers or mixed use cases
   If you use the same phone number for different campaign types (for example, promotions + notifications + reminders), carriers may treat that as mixed use, typically with lower trust/throughput or steeper fees.
   
   
7. Industry-specific restrictions
   Some verticals are more scrutinized (e.g. financial services, healthcare, debt collection, adult content). Sample messages, privacy rules, possibly extra compliance required.
   
   

How to Properly Register — Step-by-Step Technical Guide

If you were to register yourself (or understand what a service like Meera handles for you), here are the technical steps:

• Legal name, incorporation docs, tax/EIN or equivalent if non-US
• Registered address, website domain, vertical / industry classification
• Contact info, authorized representative(s)

2. Prepare campaign(s)

• Define each use case: marketing, promotions, transactional, notifications etc.
• Write sample messages you intend to send (one or two) including opt-in/out language, sender identity, etc.
• Document how members opt in (web signup, email form, checkbox, SMS keyword, etc.)
  
  

3. Brand registration via Campaign Registry (TCR)

• Submit above business info to be verified. Ensure consistency with public records.
• Wait for approval. Might require supplemental documentation.
  
  
  

• Submit use case + sample messages + opt-in details.
• Wait for review from TCR / DCA (Direct Carrier Aggregators).

5. Associate phone numbers

• Link the long code / number(s) you’ll send from to the campaign(s).
  
  

6. Set up sending infrastructure / SMS provider compliance

• Ensure your SMS service provider or platform supports 10DLC registration and correctly routes traffic.
• Configure your message templates, opt-out handling, sender identity (e.g., the “from” name / number) per requirements.
  
  

7. Monitor & maintain

• Track delivery, opt-outs, complaint rates.
• Keep registration up to date (if business info / use cases change)
• Be ready to respond if campaign is flagged or rejections happen.
  
  

Seems complicated? You’re not alone. 

Even for experienced marketers, SMS registration is not straightforward. Carriers require precise brand information, vetted use cases, sample messages that meet compliance standards, and proper phone number associations. A small mistake—an EIN mismatch, an unclear opt-in process, or the wrong campaign category—can delay or derail your approval.

That’s why Meera builds registration support into every deployment. Our AI experts handle the entire process of getting your brand approved with carriers so your campaigns actually get delivered. That includes:

• Collecting and validating your business information for brand approval
• Registering your campaigns and local numbers with The Campaign Registry
• Flagging compliance issues (like opt-in wording or website gaps) before they trigger rejections

And that’s just a piece of what goes into launching a successful AI texting campaign. From script writing and testing, to CRM integration and ongoing optimization, Meera’s team ensures your campaigns aren’t just registered—they’re compliant, effective, and ready to scale.

The result? Your texts get delivered, not filtered, so your team can focus on conversations instead of carrier forms.