SignalSMS API Reference

Authentication

All API requests require a valid Bearer token in the Authorization header. Generate your API key from the Dashboard → Developer Credentials panel.

# Include this header in every request
Authorization: Bearer sig_live_9a2f1b8c0d9238f90c8831aee892bbcc00fa

Rate Limits

The API enforces rate limits to ensure fair usage and platform stability. Limits are applied per API key.

Dispatch SMS

curl -X POST https://api.signalsms.com/v1/sms/dispatch \
  -H "Authorization: Bearer sig_live_9a2f1b8c..." \
  -H "Content-Type: application/json" \
  -d '{
    "sender": "WhiteRaven",
    "recipients": ["+14155552671", "+447700900123"],
    "message": "Your verification code is 482910.",
    "fast_dispatch": true
  }'

import requests

payload = {
    "sender": "WhiteRaven",
    "recipients": ["+14155552671", "+447700900123"],
    "message": "Your verification code is 482910.",
    "fast_dispatch": True
}

headers = {
    "Authorization": "Bearer sig_live_9a2f1b8c...",
    "Content-Type": "application/json"
}

response = requests.post(
    "https://api.signalsms.com/v1/sms/dispatch",
    json=payload,
    headers=headers
)

print(response.json())

JSON.stringify({
    sender: "WhiteRaven",
    recipients: ["+14155552671", "+447700900123"],
    message: "Your verification code is 482910.",
    fast_dispatch: true
  })
});

const data = await response.json();
console.log(data);

<?php
$ch = curl_init("https://api.signalsms.com/v1/sms/dispatch");

curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POST           => true,
    CURLOPT_HTTPHEADER     => [
        "Authorization: Bearer sig_live_9a2f1b8c...",
        "Content-Type: application/json"
    ],
    CURLOPT_POSTFIELDS     => json_encode([
        "sender"     => "WhiteRaven",
        "recipients" => ["+14155552671", "+447700900123"],
        "message"    => "Your verification code is 482910.",
        "fast_dispatch" => true
    ])
]);

$response = curl_exec($ch);
curl_close($ch);

echo $response;

{
  "status": "queued",
  "message_id": "msg_7f8a2b4c1e9d3a56",
  "recipients_count": 2,
  "segments": 1,
  "cost": "0.046",
  "currency": "EUR",
  "remaining_balance": "124.454"
}

Check Delivery Status

{
  "message_id": "msg_7f8a2b4c1e9d3a56",
  "status": "delivered",
  "created_at": "2026-05-30T14:22:10Z",
  "delivered_at": "2026-05-30T14:22:12Z",
  "reports": [
    {
      "recipient": "+14155552671",
      "status": "delivered",
      "carrier": "T-Mobile US",
      "latency_ms": 1840
    },
    {
      "recipient": "+447700900123",
      "status": "delivered",
      "carrier": "Vodafone UK",
      "latency_ms": 2310
    }
  ]
}

Wallet Balance

{
  "balance": "124.50",
  "currency": "USDT",
  "last_topup": "2026-05-28T10:15:00Z",
  "last_topup_amount": "50.00"
}

Rate Lookup

{
  "rates": [
    { "country": "US", "name": "United States", "price_eur": 0.018, "route": "direct" },
    { "country": "DE", "name": "Germany", "price_eur": 0.068, "route": "direct" },
    { "country": "GB", "name": "United Kingdom", "price_eur": 0.028, "route": "direct" }
  ]
}

Sender IDs

{
  "senders": [
    { "name": "WhiteRaven", "status": "approved", "created_at": "2026-05-10T08:00:00Z" },
    { "name": "SignalSMS", "status": "approved", "created_at": "2026-04-22T12:30:00Z" }
  ]
}

Webhooks

Receive real-time delivery status updates via HTTP POST to your server. Configure your webhook URL per-message using the callback_url parameter, or set a global webhook URL in your dashboard settings.

Webhook Payload Example

{
  "event": "sms.delivered",
  "message_id": "msg_7f8a2b4c1e9d3a56",
  "recipient": "+14155552671",
  "status": "delivered",
  "carrier": "T-Mobile US",
  "delivered_at": "2026-05-30T14:22:12Z",
  "latency_ms": 1840
}

Error Codes

The API uses standard HTTP status codes. Errors include a JSON body with error and message fields.

{
  "error": "unauthorized",
  "message": "Invalid or expired API key. Generate a new key from Dashboard → Developer Credentials."
}