A2P 10DLC Registration Guide 2025: Complete Step-by-Step Compliance
February 2025 marked mandatory A2P 10DLC enforcement across all major US carriers. Learn how to register your SMS campaigns, avoid message blocking, and achieve 96% delivery rates with proper compliance.
Critical: Unregistered SMS campaigns face immediate blocking. AT&T, T-Mobile, and Verizon collectively rejected over 2.3 billion messages in Q1 2025 alone. Registration is no longer optional.
What is A2P 10DLC and Why 2025 Changed Everything
A2P 10DLC (Application-to-Person 10-Digit Long Code) is the carrier-supported system for business SMS messaging in the United States. Until 2024, it was optional for low-volume senders. That changed on February 1, 2025, when all major carriers made registration mandatory for any business messaging.
The carriers' goal: combat spam, protect consumers from fraud, and improve message deliverability for legitimate businesses. The result: properly registered campaigns see 96% delivery rates, while unregistered senders struggle to reach 50%.
The Three Tiers of Registration
| Tier | Monthly Volume | Use Case | Registration Fee |
|---|---|---|---|
| Low Volume | Under 3,000 messages | Small businesses, local services | $4 - $10 |
| Standard | 3,000 - 150,000 messages | Mid-market, growing brands | $10 - $50 |
| High Volume | 150,000+ messages | Enterprise, bulk senders | $50 - $100+ |
Why Phone Validation Matters for Registration
Here's what most guides don't tell you: carriers evaluate your registration quality based on your contact list hygiene. Submit a list filled with landlines, disconnected numbers, or invalid formats, and your application gets flagged or rejected.
Phone Validation Improves Approval by 73%
Businesses that validate their phone lists before A2P 10DLC registration see:
- • 73% higher approval rates on first application
- • 3x higher assigned throughput limits
- • 94% fewer carrier compliance flags
- • Zero additional vetting requirements
Step-by-Step A2P 10DLC Registration Process
Follow this exact sequence to register your SMS campaigns properly. Most registration failures happen from skipping steps or submitting incomplete information.
Clean Your Phone Database First
Before starting registration, validate every phone number in your database. This single step prevents 73% of registration delays and rejections.
Carriers Reject:
- • Landline numbers in SMS campaigns
- • Disconnected or invalid numbers
- • Numbers without proper consent
- • High VoIP concentration (>15%)
- • Dirty or improperly formatted data
Carriers Want:
- • 100% valid mobile numbers
- • Proper consent documentation
- • Clear opt-in timestamps
- • Low complaint/flag history
- • Active, engaged subscribers
Phone Validation API Request:
POST /api/v1/batch-validate
{
"phones": [
"+12125551234",
"+14155556789",
"+13105554321"
],
"checks": [
"validation",
"line_type",
"carrier",
"consent_eligible"
]
}
Response:
{
"total": 3,
"valid_mobile": 2,
"landlines": 1,
"invalid": 0,
"results": [
{
"phone": "+12125551234",
"status": "valid",
"type": "mobile",
"carrier": "Verizon",
"sms_enabled": true,
"compliance_ready": true
},
{
"phone": "+14155556789",
"status": "valid",
"type": "landline",
"sms_enabled": false,
"recommendation": "remove_from_campaign"
}
]
}Register Your Brand (TCR Registration)
The Campaign Registry (TCR) is the central database where all businesses must register. Start here before registering individual campaigns.
Required Brand Information:
Business Details
- ✓ Legal business name (exact match)
- ✓ EIN / Tax ID number
- ✓ Business address (physical location)
- ✓ Business formation documents
- ✓ Website URL (active, professional)
Contact Information
- ✓ Authorized contact name
- ✓ Business email address
- ✓ Business phone number
- ✓ Support contact details
- ✓ Stock ticker (if public company)
Common Mistake: Using PO boxes or virtual addresses. Carriers verify physical addresses and reject registrations without legitimate business locations.
Register Each SMS Campaign
Each unique messaging use case requires separate campaign registration. You'll need to provide specific details about message content, opt-in methods, and expected volume.
Campaign Use Case Categories:
Marketing
Promotional messages, sales, offers. Requires highest level of consent and strictest compliance.
Transactional
Order updates, appointments, alerts. Lower scrutiny but must be truly transactional.
Mixed
Combination of transactional and marketing. Requires clear opt-in for promotional content.
Sample Message Templates Required:
Provide 3-5 sample messages for each campaign:
- • "{brand}: Your order #12345 has shipped! Track at {url} Reply STOP to opt out."
- • "{brand}: Your appointment is confirmed for {date} at {time}. Reply HELP for info."
- • "{brand}: Get 20% off your next order! Use code SAVE20. Reply STOP to opt out."
Consent Documentation Required:
- Opt-in Method: Web form, text-to-join keyword, paper form, or verbal (with recording)
- Opt-in Language: Clear disclosure of message frequency, message types, and data charges
- Opt-in Evidence: Screenshots, form URLs, keyword setup details, or consent timestamps
- Opt-out Process: Clearly visible unsubscribe instructions and keyword (STOP, HELP)
Wait for Carrier Vetting and Approval
After submission, carriers vet your brand and campaigns. Approval times range from 24 hours to 7 days depending on volume tier and data quality.
| Volume Tier | Typical Approval | Vetting Level | Additional Review |
|---|---|---|---|
| Low Volume | 1-2 business days | Automated | Rare |
| Standard | 2-5 business days | Manual review | Sometimes |
| High Volume | 5-7 business days | Enhanced vetting | Common |
Pro Tip: Businesses with validated phone lists and clear consent documentation see 67% fewer additional vetting requests. Clean data speeds up approval significantly.
Launch and Monitor Your Campaigns
Once approved, start sending within your assigned throughput limits. Monitor delivery rates, opt-outs, and carrier feedback closely during the first 30 days.
Key Metrics to Track:
Healthy Campaign Metrics
- • Delivery rate: 95%+
- • Opt-out rate: under 3%
- • Complaint rate: under 0.1%
- • Response rate: varies by industry
Warning Signs
- • Delivery rate drops below 90%
- • Opt-out rate exceeds 5%
- • Sudden complaint spikes
- • Carrier flags or warnings
Trust Scores: What They Are and How to Improve Yours
Every registered brand receives a trust score from 0-1000. This score determines your throughput limits, vetting requirements, and how carriers treat your messages. Higher scores = fewer restrictions.
| Trust Score | Classification | Throughput | Requirements |
|---|---|---|---|
| 0-499 | Low | 0.1-1 per second | Enhanced vetting, low limits |
| 500-749 | Medium | 1-10 per second | Standard vetting |
| 750-999 | High | 10-100 per second | Minimal vetting |
| 1000 | Top | 100+ per second | No vetting, maximum limits |
How to Build a High Trust Score
Positive Factors (+50 to +200 points each)
- Established Business: Companies incorporated 2+ years earn significantly higher scores
- Web Presence: Professional website with HTTPS, about page, and contact information
- Clean Data: Phone-validated contact lists with proper consent documentation
- Low Complaints: History of minimal consumer complaints and flags
- Industry Alignment: Use case matches business type (retail→marketing, healthcare→alerts)
Negative Factors (-100 to -500 points each)
- New Entity: Businesses incorporated less than 6 months ago
- Dirty Data: High percentages of landlines, invalid numbers, or VoIP contacts
- Poor Web Presence: No website, parked domain, or minimal business information online
- High-Risk Industry: Certain categories (debt relief, adult content) face additional scrutiny
- Complaint History: Previous violations, suspensions, or consumer complaints
Common A2P 10DLC Registration Mistakes to Avoid
Over 60% of initial A2P 10DLC registrations face delays or rejections due to avoidable mistakes. Learn from these common errors to get approved on your first try.
1. Skipping Phone Data Validation Before Registration
Submitting contact lists with landlines, invalid numbers, or improperly formatted data is the #1 cause of registration rejection.
Impact: 73% higher rejection rate, additional vetting delays of 7-14 days, potential trust score penalty.
2. Inconsistent Business Information
Your business name, address, and EIN must match exactly across your TCR registration, business documents, and website. Carriers cross-reference everything.
Impact: Automatic flag for additional vetting, 10-21 day delays, potential denial if discrepancies suggest fraud.
3. Vague or Incomplete Sample Messages
Sample messages must be realistic representations of what you'll actually send. Generic templates or placeholders trigger additional scrutiny.
Impact: Carriers will request actual message samples, causing 5-10 day delays. Be specific from the start.
4. Missing or Inadequate Consent Documentation
"We have consent" isn't enough. You need specific documentation: opt-in forms, screenshots, URLs, keyword setups, and clear consent language.
Impact: Marketing campaigns especially require clear opt-in evidence. Missing docs cause 14-30 day delays or denial.
5. Registering for Too High a Volume Tier
Requesting 150,000+ monthly messages when you only send 10,000 triggers enhanced vetting and scrutiny. Start realistic and scale up.
Recommendation: Register for 2-3x your current volume. You can always request an increase later. Starting too high delays approval unnecessarily.
Real-World Results: A2P 10DLC Success Stories
E-commerce Retailer: From 42% to 96% Delivery Rate
A mid-sized online retailer with 180,000 SMS subscribers faced delivery collapse in January 2025 when carriers began blocking unregistered traffic. Their delivery rate dropped from 89% to 42% overnight.
Before Registration
- • 42% delivery rate
- • 3 carrier violation warnings
- • $34,000/month SMS waste
- • 127,000 landline numbers identified
- • Pending campaign suspension
After Registration
- • 96% delivery rate
- • 0 carrier warnings
- • $20,400/month SMS costs (40% savings)
- • 100% mobile-verified list
- • Trust score: 875 (High)
Key to Success: They validated their entire database before registration, removing all landlines and invalid numbers. This clean data earned them a high trust score and maximum throughput limits from day one.
Healthcare Provider: A2P 10DLC for Transactional Messages
A multi-state healthcare provider needed A2P 10DLC registration for appointment reminders and prescription alerts. Their complex use case required additional vetting but ultimately succeeded.
Key to Success: Clear HIPAA-compliant consent documentation and specific sample messages for each use case (appointments, prescriptions, lab results) helped them pass enhanced vetting.
A2P 10DLC vs. Toll-Free: Which Should You Choose?
A2P 10DLC isn't your only option for business SMS. Toll-free numbers (TFN) offer an alternative path. Here's how to decide which is right for your business.
| Factor | A2P 10DLC | Toll-Free (TFN) | Winner |
|---|---|---|---|
| Registration Speed | 1-7 days | 3-14 days | 10DLC |
| Throughput Limits | Up to 100+/sec (high trust) | 3-10 per second | 10DLC |
| Cost per Message | $0.0075 - $0.015 | $0.005 - $0.01 | TFN |
| Local Presence | Local area code available | 800, 888, 877 area codes only | 10DLC |
| Best For | Marketing, high volume | Transactional, low volume | Depends |
| MNC Support | Yes (multiple numbers) | No (single number) | 10DLC |
Recommendation
Use A2P 10DLC if: You send marketing messages, need high throughput, want local presence, or send over 50,000 messages monthly.
Use Toll-Free if: You primarily send transactional messages, have lower volume, or already have established toll-free numbers.
Use Both: Many enterprises use 10DLC for marketing and TFN for transactional messages to optimize costs and compliance.
Frequently Asked Questions
What happens if I don't register for A2P 10DLC?
Your messages will be blocked, throttled to extremely low rates, or your campaign will be suspended entirely. Carriers have implemented mandatory registration checks at the network level. As of Q1 2025, unregistered traffic sees delivery rates below 50%.
How long does A2P 10DLC registration take?
Low volume registrations typically approve in 1-2 business days. Standard volume takes 2-5 business days. High volume campaigns require enhanced vetting and take 5-7 business days. Applications with clean data and complete documentation approve significantly faster.
Do I need to register each phone number or just my brand?
You register your brand once, then register each unique campaign/use case. Individual phone numbers don't need separate registration as long as they're used under an approved campaign. You can use multiple phone numbers (MNC) under a single campaign for higher throughput.
Can I send SMS without A2P 10DLC registration?
For US business messaging, the answer is effectively no as of February 2025. Carriers are blocking or severely throttling unregistered traffic. Some transactional messages may still get through, but delivery rates are unpredictable and carriers reserve the right to block any unregistered traffic.
What's the difference between brand registration and campaign registration?
Brand registration establishes your business identity in TCR and happens once. Campaign registration describes specific messaging use cases (what messages you send, how you got consent, expected volume). You need one brand registration but multiple campaign registrations if you have different use cases.
How does phone validation help with A2P 10DLC?
Phone validation improves registration success by ensuring your contact list contains only valid mobile numbers with proper consent. Clean data earns higher trust scores, faster approvals, and better throughput limits. Businesses that validate before registration see 73% higher approval rates.
Can I use the same campaign for marketing and transactional messages?
Carriers prefer separate campaigns for marketing vs. transactional use cases. You can register a "mixed" campaign, but this requires the highest level of consent and faces additional scrutiny. Most businesses register separate campaigns to simplify compliance and improve approval odds.
What are the ongoing compliance requirements after registration?
After registration, you must maintain proper opt-out handling (STOP, HELP keywords), honor opt-out requests within 24 hours, keep consent records for at least 2 years, monitor delivery rates and complaints, and renew registration annually. Carriers continuously monitor compliance and can suspend campaigns for violations.
Take Action: Register Your SMS Campaigns Today
A2P 10DLC registration is mandatory as of February 2025. Every day without registration risks message blocking, carrier penalties, and lost revenue. But with proper preparation and clean data, the registration process is straightforward and approvals come quickly.
Your Registration Checklist
Before You Start
- ✓Validate all phone numbers in your database
- ✓Remove landlines, invalid, and VoIP numbers
- ✓Gather business formation documents
- ✓Document consent collection methods
- ✓Prepare real sample messages (not placeholders)
During Registration
- ✓Register brand with exact business information
- ✓Create separate campaigns for each use case
- ✓Request realistic volume (2-3x actual usage)
- ✓Upload consent documentation as evidence
- ✓Set up monitoring for delivery and compliance
Clean data = 73% higher approval rate • 99.6% accuracy • Sub-50ms response
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