One API Call to Send SMS via Twilio

The Twilio API requires phone number provisioning, A2P 10DLC registration for US messaging, and compliance with carrier filtering rules. RelayAPI handles OAuth, rate limits, media hosting, and API changes.

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POST /v1/posts
const response = await fetch('https://api.relayapi.dev/v1/posts', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer rlay_live_xxxxxxxxxx',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    content: 'Check out our latest update!',
    platforms: ['twilio'],
    media: ['https://cdn.example.com/image.jpg'],
  }),
});

Twilio API

  • A2P 10DLC registration for US messaging requires brand registration, campaign vetting, and can take days to weeks
  • Phone number provisioning, compliance bundles, and messaging service configuration add significant setup overhead
  • Carrier filtering and deliverability vary by carrier, content type, and sending volume with limited visibility
  • Pricing is complex with per-segment charges, carrier fees, and different rates for domestic vs international messages
  • Handling delivery status callbacks, opt-out management (STOP/START), and error codes requires webhook infrastructure

RelayAPI

  • RelayAPI guides you through A2P 10DLC registration and handles brand/campaign setup for US messaging compliance
  • We manage phone number provisioning, messaging service configuration, and compliance bundles on your behalf
  • Built-in deliverability monitoring with carrier filtering detection, content optimization, and throughput management
  • Transparent pricing with per-message cost estimates and automatic segment optimization to reduce costs
  • We handle delivery callbacks, opt-out compliance (STOP/START), and error recovery so you get clean status updates
Save 3+ hours of development time

A2P 10DLC Registration Required for US Messaging

Sending SMS to US numbers requires A2P 10DLC registration with carrier-verified brand and campaign information. Messages sent without registration may be filtered or blocked by carriers.

Supported Content Types

SMSMMSWhatsApp via TwilioShort Codes

How It Works

1

Connect Your Account

Authorize your Twilio SMS account via OAuth in 30 seconds

2

Build Your Integration

Use the REST API or our SDKs to publish content

3

RelayAPI Handles the Rest

We manage publishing, rate limits, and delivery notifications

Ship Faster

Send SMS and MMS with a single API call. No phone number provisioning, no A2P registration management, no webhook infrastructure. Specify the recipient and message, we handle delivery.

Official API, Zero Hassle

RelayAPI uses the official Twilio API. Your messages are delivered through Twilio's global network with full delivery tracking, while we handle compliance, phone numbers, and carrier requirements.

Deliverability Optimization

Carrier filtering is the biggest challenge in SMS. RelayAPI monitors deliverability, detects filtering patterns, optimizes message content, and manages sending throughput to maximize delivery rates.

Frequently Asked Questions

Start Building with Twilio SMS

Join developers who chose RelayAPI over building with Twilio API directly.

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