Puerto Rico SMS Guide: Regulations, Compliance & Best Practices (2025)

Learn how to send SMS messages to Puerto Rico while maintaining compliance with US federal regulations. This comprehensive guide covers 10DLC registration requirements, TCPA compliance rules, carrier integration (Claro, T-Mobile, Liberty, AT&T), and best practices for reaching Puerto Rico's 2.70 million mobile connections (82.7% penetration rate).

Puerto Rico SMS Quick Reference Guide

Market Overview:

• Connections: 2.70 million (82.7% penetration, January 2024)
• Major Carriers: Claro (~2.5M subscribers), T-Mobile, Liberty, AT&T
• Dialing Code: +1
• Area Codes: 787 and 939 (overlay covering entire territory)
• Time Zone: Atlantic Standard Time (AST, UTC-4, no Daylight Saving Time)

Compliance Requirements:

• 10DLC Registration: Mandatory for all long codes (1-3 business days typical)
• Regulations: TCPA, CTIA Messaging Principles (same as US mainland)
• Consent: Explicit opt-in required for marketing messages
• Opt-Out Keywords: STOP, QUIT, CANCEL, UNSUBSCRIBE, HELP (English and Spanish)
• Messaging Hours: 8:00 AM - 8:00 PM AST for marketing

Number Formatting:

• E.164 format required: +1787XXXXXXX or +1939XXXXXXX
• 10-digit dialing mandatory within Puerto Rico

Key Features:

• Two-way SMS: Fully supported
• Concatenated messages: Not supported
• MMS: Converted to SMS with media URL
• Number portability: Not available

Understanding the Puerto Rico SMS Market

Market Conditions:

SMS ensures reliable delivery across all carriers, while OTT messaging apps remain popular for personal communication only.

Sources: DataReportal Digital 2024: Puerto Rico (population and connection statistics, January 2024), BNamericas Puerto Rico mobile market analysis (2024), Statista mobile provider survey (2020), Opensignal Puerto Rico Mobile Network Experience Report (May 2023)

SMS Features and Capabilities in Puerto Rico

Puerto Rico supports comprehensive SMS capabilities including two-way messaging, with features and regulations aligned with US mainland standards.

Two-way SMS Support

Two-way SMS is fully supported. Use it for:

• Customer service interactions
• Appointment confirmations with reply options
• Survey responses
• Order status updates with delivery confirmations

No special restrictions apply beyond standard US messaging regulations.

Concatenated Messages (Segmented SMS)

Support: Concatenated messaging is not supported through the Sent.dm platform for Puerto Rico. Message length rules: Messages follow standard SMS character limits – 160 characters for GSM-7 encoding and 70 characters for Unicode (UCS-2). Encoding considerations: Both GSM-7 and UCS-2 encodings are supported, with GSM-7 recommended for standard ASCII characters to maximize message length.

Character Encoding Comparison:

MMS Support

MMS messages are automatically converted to SMS with an embedded URL link to the media content.

Supported Media Types: Images (JPEG, PNG, GIF), videos (MP4, MOV), audio (MP3, AAC) File Size Limit: 5 MB maximum URL Expiration: Links expire after 30 days

How Do Puerto Rico Phone Numbers Work?

Number Portability

Number portability is not available in Puerto Rico. Phone numbers remain tied to their original carriers, which can help ensure more reliable message routing.

Sending SMS to Landlines

Sending SMS to landline numbers is not supported. Attempts return error code 21614:

{
  "code": 21614,
  "message": "'To' number is not a valid mobile number",
  "status": 400
}

No charges apply for failed landline deliveries.

Area Code Coverage

Puerto Rico uses area codes 787 and 939 as overlays, meaning both codes cover the entire territory rather than dividing it geographically. Area code 787 was introduced on March 1, 1996, and area code 939 was added as an overlay on September 15, 2001, due to number exhaustion. 10-digit dialing is mandatory within Puerto Rico for all calls and SMS messages.

Phone numbers must be formatted in E.164 format for international routing: +1787XXXXXXX or +1939XXXXXXX.

Sources: Wikipedia "Telephone numbers in Puerto Rico" (area code history and structure, verified 2024), North American Numbering Plan Administration (NANPA) official documentation

Puerto Rico SMS Compliance and Regulatory Requirements

As a US territory, Puerto Rico follows US federal telecommunications regulations, including TCPA (Telephone Consumer Protection Act) and CTIA Messaging Principles & Best Practices. Businesses must comply with both federal requirements and carrier-specific rules for A2P messaging.

How to Complete A2P 10DLC Registration:

1. Create an account with The Campaign Registry (TCR)
2. Register your brand (provide EIN, business address, contact info)
3. Submit campaign use case (marketing, transactional, etc.)
4. Provide sample message templates
5. Wait for carrier approval (1-3 business days typical, up to 2 weeks for complex campaigns)
6. Receive your registered 10DLC number for SMS messaging

Required for: All US recipients, including Puerto Rico, Virgin Islands, Guam, and American Samoa

Sources: The Campaign Registry official documentation (2024), CTIA Messaging Principles & Best Practices (updated 2024), FCC TCPA guidelines, Twilio A2P 10DLC compliance documentation (2024)

SMS Consent Requirements and Opt-In Best Practices

Explicit written consent is mandatory before sending any marketing or promotional SMS messages to Puerto Rico recipients.

Sample Opt-In Message:

Reply YES to receive special offers from [Brand]. Msg frequency varies. Msg & data rates may apply. Reply STOP to cancel, HELP for info.

Best Practices:

• Collect written or digital consent with clear terms
• Maintain detailed records of opt-in dates and methods
• Specify message frequency and content type
• Use double opt-in for marketing programs
• Provide clear disclosure of message and data rates

HELP/STOP and Other Commands

Required Keywords: STOP, QUIT, CANCEL, UNSUBSCRIBE, HELP (English and Spanish)

Sample STOP Response (English):

You've been unsubscribed from [Brand] messages. Reply START to resubscribe. Text HELP for assistance.

Sample STOP Response (Spanish):

Te has dado de baja de mensajes de [Brand]. Responde START para volver a suscribirte. Envía HELP para ayuda.

Sample HELP Response (English):

[Brand] - Msg frequency varies. Msg & data rates may apply. Text STOP to cancel. Help: [phone] or [email]

Requirements:

• Acknowledge opt-out requests within 24 hours
• Include program information, support contact, and message frequency

Do Not Call / Do Not Disturb Registries

Puerto Rico follows the US National Do Not Call Registry. Best practices include:

• Regularly scrubbing contact lists against the National DNC Registry
• Maintaining internal do-not-contact lists
• Implementing immediate opt-out processing
• Documenting all opt-out requests and processing dates

Puerto Rico Time Zone for SMS Scheduling (Atlantic Standard Time)

Puerto Rico observes Atlantic Standard Time (AST) year-round at UTC-4. The territory does not observe Daylight Saving Time – clocks do not change in Puerto Rico. The last DST change was on September 30, 1945.

Time relationship with US Eastern Time:

• During US Daylight Saving Time (March–November): Puerto Rico is the same time as Eastern Daylight Time (EDT)
• During US Standard Time (November–March): Puerto Rico is one hour ahead of Eastern Standard Time (EST)

Timezone Conversion Example (JavaScript/TypeScript):

import { DateTime } from 'luxon';

// Convert to Atlantic Standard Time (AST)
const now = DateTime.now().setZone('America/Puerto_Rico');
const hour = now.hour;

// Check if within allowed hours (8 AM - 8 PM AST)
const isWithinBusinessHours = hour >= 8 && hour < 20;

if (!isWithinBusinessHours) {
  // Schedule message for next day at 9 AM AST
  const nextSend = now.plus({ days: 1 }).set({ hour: 9_ minute: 0 });
  console.log(`Message scheduled for: ${nextSend.toISO()}`);
}

Recommended Messaging Hours:

• Standard Business Hours: 8:00 AM – 8:00 PM AST (UTC-4)
• Emergency Messages: Allowed 24/7 for critical notifications
• Marketing Messages: Restrict to business hours only
• Consider Holidays: Respect local holidays and cultural observances

Sources: TimeAndDate.com "Time Zones in Puerto Rico" (official time zone data_ verified 2024)_ US Naval Observatory (UTC offset verification)

Phone Number Types for Puerto Rico SMS (10DLC_ Short Codes_ Toll-Free)

Alphanumeric Sender ID

Operator network capability: Not supported for dynamic usage Registration requirements: Not applicable Sender ID preservation: Not preserved – messages will display numeric sender ID

Long Codes

Domestic vs. International:

• Domestic long codes supported with required 10DLC registration
• International long codes not supported

Sender ID preservation: Yes_ for registered 10DLC numbers Provisioning time: 1-3 business days for 10DLC registration (typical)_ up to 2 weeks for complex campaigns Use cases:

• Two-factor authentication
• Appointment reminders
• Customer service
• Transactional messages

10DLC Registration Requirements:

All businesses using 10-digit long codes must register with The Campaign Registry (TCR) before sending A2P SMS messages.

Source: The Campaign Registry official documentation (2024)_ CTIA A2P 10DLC requirements (2023-2024)

Short Codes

Support: US short codes supported by major carriers (Claro_ T-Mobile_ Liberty_ AT&T) Provisioning time: 8-12 weeks for new short code approval Use cases:

• High-volume marketing campaigns
• Time-sensitive alerts
• Mass notifications
• Promotional campaigns

Restricted Content and Filtering Rules for Puerto Rico SMS

Prohibited Content:

• Gambling and lottery services
• Adult content or SHAFT (Sex_ Hate_ Alcohol_ Firearms_ Tobacco)
• Cryptocurrency promotions
• Debt collection
• Political messaging without proper disclosure

Content Filtering

Carrier Filtering Rules:

• Messages containing prohibited keywords are blocked
• URLs must be from approved domains
• High-frequency messaging may trigger spam filters

Best Practices to Avoid Filtering:

• Avoid URL shorteners
• Use registered domains
• Maintain consistent sending patterns
• Include clear business identification
• Avoid excessive punctuation and all-caps

Common Filtering Issues & Solutions:

Best Practices for Sending SMS Messages to Puerto Rico

Messaging Strategy

• Keep messages under 160 characters when possible
• Include clear call-to-actions
• Use personalization tokens thoughtfully
• Maintain consistent sender identification

Sending Frequency and Timing

Optimal Sending Times by Industry:

• Limit marketing messages to 2-4 per month per recipient
• Respect quiet hours (8 PM – 8 AM AST)
• Avoid sending during major holidays
• Space out bulk campaigns to prevent network congestion

Localization

Puerto Rican Holidays to Avoid:

• January 6: Three Kings Day (Día de Reyes)
• July 25: Constitution Day
• November 19: Discovery of Puerto Rico Day
• US federal holidays (New Year's_ Memorial Day_ Independence Day_ Labor Day_ Thanksgiving_ Christmas)

Cultural Considerations:

• Family-oriented messaging resonates well

• Use formal greetings for professional contexts

• Acknowledge both Spanish and English language preferences

• Offer messages in both Spanish and English

• Consider cultural context and local preferences

• Use appropriate date and time formats

• Include local contact information when possible

Opt-Out Management

• Process opt-outs in real-time
• Maintain centralized opt-out database
• Confirm opt-outs with acknowledgment message
• Regular audit of opt-out list compliance

Testing and Monitoring

Key Metrics to Track:

• Test across major carriers (Claro, T-Mobile, Liberty, AT&T)
• Monitor delivery rates by carrier
• Track opt-out rates and patterns
• Regular testing of opt-out functionality
• Monitor for carrier filtering changes

SMS API Integration for Puerto Rico (Twilio, Sinch, MessageBird, Plivo)

Twilio SMS API for Puerto Rico

Twilio provides robust SMS API support for sending messages to Puerto Rico phone numbers. Get your Account SID and Auth Token from the Twilio Console to get started.

import { Twilio } from 'twilio';

// Initialize Twilio client with credentials
const client = new Twilio(
  process.env.TWILIO_ACCOUNT_SID,
  process.env.TWILIO_AUTH_TOKEN
);

// Function to send SMS to Puerto Rico
async function sendSMSToPuertoRico(
  to: string,
  message: string
): Promise<void&gt; {
  try {
    // Ensure number is in E.164 format for Puerto Rico (+1787XXXXXXX or +1939XXXXXXX)
    const formattedNumber = to.startsWith('+1') ? to : `+1${to}`;

    const response = await client.messages.create({
      body: message,
      to: formattedNumber,
      from: process.env.TWILIO_PHONE_NUMBER, // Your registered 10DLC or shortcode
      statusCallback: 'https://your-webhook.com/status', // Optional delivery status updates
    });

    console.log(`Message sent successfully! SID: ${response.sid}`);
  } catch (error: any) {
    // Handle specific Twilio error codes
    if (error.code === 21614) {
      console.error('Invalid mobile number (possibly landline)');
    } else if (error.code === 21211) {
      console.error('Invalid phone number format');
    } else if (error.code === 21408) {
      console.error('Rate limit exceeded, implement backoff');
    } else {
      console.error('Error sending message:', error.message);
    }
    throw error;
  }
}

Sinch SMS API Integration

Sinch offers SMS messaging capabilities for Puerto Rico through their REST API, requiring an API Token and Service Plan ID.

import axios from 'axios';

class SinchSMSService {
  private readonly apiToken: string;
  private readonly servicePlanId: string;
  private readonly baseUrl: string = 'https://us.sms.api.sinch.com/xms/v1';

  constructor(apiToken: string, servicePlanId: string) {
    this.apiToken = apiToken;
    this.servicePlanId = servicePlanId;
  }

  async sendSMS(to: string, message: string): Promise<void&gt; {
    try {
      const response = await axios.post(
        `${this.baseUrl}/${this.servicePlanId}/batches`,
        {
          from: process.env.SINCH_SENDER_ID,
          to: [to],
          body: message
        },
        {
          headers: {
            'Content-Type': 'application/json',
            Authorization: `Bearer ${this.apiToken}`
          }
        }
      );

      console.log('Message sent successfully:', response.data.id);
    } catch (error) {
      console.error('Failed to send message:', error);
      throw error;
    }
  }
}

MessageBird SMS API for Puerto Rico

MessageBird provides SMS API access for Puerto Rico messaging with straightforward integration options.

import { MessageBird } from 'messagebird';

class MessageBirdService {
  private client: MessageBird;

  constructor(apiKey: string) {
    this.client = new MessageBird(apiKey);
  }

  async sendSMS(to: string, message: string): Promise<void&gt; {
    const params = {
      originator: process.env.MESSAGEBIRD_SENDER_ID,
      recipients: [to],
      body: message,
      reportUrl: 'https://your-webhook.com/delivery-reports'
    };

    return new Promise((resolve, reject) =&gt; {
      this.client.messages.create(params, (err, response) =&gt; {
        if (err) {
          console.error('Error sending message:', err);
          reject(err);
        } else {
          console.log('Message sent successfully:', response.id);
          resolve();
        }
      });
    });
  }
}

Plivo SMS API Integration for Puerto Rico

Plivo's SMS API provides reliable message delivery to Puerto Rico phone numbers with detailed delivery tracking and status callbacks.

import plivo from 'plivo';

class PlivoSMSService {
  private client: plivo.Client;

  constructor(authId: string, authToken: string) {
    this.client = new plivo.Client(authId, authToken);
  }

  async sendSMS(to: string, message: string): Promise<void&gt; {
    try {
      const response = await this.client.messages.create({
        src: process.env.PLIVO_SOURCE_NUMBER, // Your Plivo number
        dst: to,
        text: message,
        url: 'https://your-webhook.com/delivery-status'
      });

      console.log('Message sent successfully:', response.messageUuid);
    } catch (error) {
      console.error('Failed to send message:', error);
      throw error;
    }
  }
}

API Rate Limits and Throughput

• Standard Rate Limits:
  • 10DLC: 1-2 messages per second
  • Short codes: Up to 100 messages per second
  • Toll-free numbers: 3 messages per second

Throughput Management Example (Redis Queue):

import Redis from 'ioredis';

const redis = new Redis();

async function queueMessage(to: string, message: string) {
  await redis.lpush('sms_queue', JSON.stringify({ to, message, timestamp: Date.now() }));
}

async function processQueue(rateLimitPerSecond: number = 2) {
  while (true) {
    const item = await redis.rpop('sms_queue');
    if (item) {
      const { to, message } = JSON.parse(item);
      await sendSMSToPuertoRico(to, message);
      await new Promise(resolve => setTimeout(resolve, 1000 / rateLimitPerSecond));
    }
  }
}

Strategies:

• Implement exponential backoff for retries
• Use message queuing systems (Redis, RabbitMQ)
• Batch messages for optimal throughput
• Monitor carrier feedback for delivery optimization

Error Handling and Reporting

Common API Error Codes:

• Implement comprehensive error logging
• Monitor delivery receipts via webhooks
• Track common error codes and responses
• Set up alerts for unusual error rates
• Maintain delivery status dashboard

Frequently Asked Questions About Puerto Rico SMS

Do I need 10DLC registration to send SMS in Puerto Rico?

Yes. 10DLC registration is mandatory for all businesses using 10-digit long codes to send Application-to-Person (A2P) SMS messages to Puerto Rico. As a US territory, Puerto Rico follows the same A2P 10DLC requirements as the US mainland. You must register your brand and campaign with The Campaign Registry (TCR) before sending messages. The registration process typically takes 1-3 business days, though complex campaigns can take up to two weeks. This requirement became mandatory industry-wide in July 2023.

What carriers operate in Puerto Rico?

Puerto Rico's mobile market is served by four major carriers: Claro (América Móvil, the market leader with approximately 2.5 million subscribers), T-Mobile, Liberty (Liberty Latin America), and AT&T (which maintains a significant presence with 39.7% of survey respondents in 2020). Claro dominates with the highest coverage score (9.1) and 99.4% availability. All carriers support US short codes and 10DLC long codes for business messaging.

What time zone should I use for SMS scheduling in Puerto Rico?

Puerto Rico observes Atlantic Standard Time (AST) at UTC-4 year-round. The territory does not observe Daylight Saving Time. During US Daylight Saving Time (March–November), Puerto Rico time matches Eastern Daylight Time (EDT). During US Standard Time (November–March), Puerto Rico is one hour ahead of Eastern Standard Time (EST). Schedule marketing messages between 8:00 AM and 8:00 PM AST to comply with TCPA regulations and respect local business hours.

What are the area codes for Puerto Rico phone numbers?

Puerto Rico uses area codes 787 and 939 as overlays covering the entire territory. Area code 787 was introduced on March 1, 1996, and area code 939 was added on September 15, 2001, due to number exhaustion. Both codes serve all geographic areas of Puerto Rico without division. 10-digit dialing is mandatory for all calls and SMS messages within Puerto Rico. Format numbers in E.164 format for SMS APIs: +1787XXXXXXX or +1939XXXXXXX.

Does Puerto Rico follow US TCPA regulations?

Yes. As a US territory, Puerto Rico follows all US federal telecommunications regulations, including the Telephone Consumer Protection Act (TCPA) and CTIA Messaging Principles & Best Practices. You must obtain explicit consent before sending marketing messages, support STOP/HELP keywords in both English and Spanish, honor opt-out requests immediately, respect quiet hours (8 PM – 8 AM AST), and scrub contact lists against the US National Do Not Call Registry. Non-compliance can result in penalties up to $1,500 per violation.

Can I send concatenated or long SMS messages to Puerto Rico?

No. Concatenated messaging is not supported through most platforms for Puerto Rico. Messages are limited to standard SMS character limits: 160 characters for GSM-7 encoding and 70 characters for Unicode (UCS-2). If you need to send longer content, split messages manually or use MMS (which will be converted to SMS with an embedded URL link to the media content). Use GSM-7 encoding for standard ASCII characters to maximize message length.

Is number portability available in Puerto Rico?

No. Number portability is not available in Puerto Rico. Phone numbers remain tied to their original carriers (Claro, T-Mobile, Liberty, or AT&T). This means you can reliably determine which carrier serves a specific number based on the number's assignment history, which can help optimize message routing and delivery strategies. However, it also means customers cannot switch carriers while keeping their existing phone numbers.

What languages should I support for SMS in Puerto Rico?

Support both Spanish and English. While Spanish is the primary language spoken by the majority of Puerto Rico's population, English is also an official language and widely understood, especially in business contexts. All required opt-out keywords (STOP, QUIT, CANCEL, UNSUBSCRIBE, HELP) must be recognized in both languages. Consider offering recipients the choice of language preference and maintain consistent language throughout your messaging campaigns.

Can I send SMS to landline numbers in Puerto Rico?

No. Sending SMS to landline numbers is not supported in Puerto Rico. Attempts to send messages to landline numbers will result in a 400 response error (code 21614) through REST APIs, with no message delivery and no charges applied to your account. Always validate phone numbers before sending to ensure they are mobile numbers. Use number validation APIs or maintain clean subscriber lists that exclude landlines.

How long does 10DLC registration take for Puerto Rico?

10DLC registration typically takes 1-3 business days for standard campaigns, though complex campaigns can take up to two weeks. The process involves registering your brand with The Campaign Registry (TCR), providing business documentation (EIN, business address, contact information), creating campaign use cases (marketing, transactional, etc.), and waiting for carrier approval. Once approved, you can begin sending SMS messages to Puerto Rico at rates of 1-2 messages per second for standard 10DLC numbers.

What Should You Do Next?

You've learned the essential requirements for sending SMS in Puerto Rico as a US territory. Take these next steps to launch compliant, effective SMS campaigns:

1. Register for 10DLC: Complete brand and campaign registration through The Campaign Registry (TCR) if you haven't already – this is mandatory for all long code messaging
2. Choose Your Carrier Strategy: Test message delivery across all major Puerto Rico carriers (Claro, T-Mobile, Liberty, AT&T) to optimize routing
3. Set Up Compliance Systems: Implement opt-in/opt-out management, consent tracking, and TCPA-compliant scheduling (8 AM – 8 PM AST)
4. Format Numbers Correctly: Ensure all phone numbers use E.164 format (+1787XXXXXXX or +1939XXXXXXX) for reliable delivery
5. Implement Bilingual Support: Configure systems to handle both Spanish and English opt-out keywords and help messages
6. Monitor Delivery Metrics: Track delivery rates, opt-out patterns, and carrier-specific performance to optimize campaigns
7. Review TCPA Guidelines: Familiarize yourself with current TCPA regulations and CTIA best practices to avoid penalties

Key Compliance Reminders:

• Maintain detailed records of opt-in dates and methods
• Process opt-out requests within 24 hours
• Respect Atlantic Standard Time (UTC-4, no DST) for scheduling
• Scrub contact lists against the National Do Not Call Registry
• Never send marketing messages to numbers without explicit consent

Additional Resources:

• FCC Guidelines
• CTIA Messaging Principles
• The Campaign Registry
• Puerto Rico Telecommunications Bureau (Junta Reglamentadora de Telecomunicaciones)
• National Do Not Call Registry

Sources: FCC official documentation, CTIA official guidelines, The Campaign Registry official site, DataReportal Digital 2024: Puerto Rico, BNamericas market analysis (2024)

Start sending compliant SMS messages to Puerto Rico today by following these guidelines and leveraging the territory's 82.7% mobile penetration rate to reach your target audience effectively.