Developer REST API Reference • Bulk5

Sub-Second SLA

Tier-1 direct telecom routes

100% DLT Compliant

Auto header & PE verification

5 Unified Channels

SMS, OTP, RCS, WhatsApp

Bearer Token Auth

Encrypted HTTPS JSON protocol

POST https://bulk5.com/api/v1/send_sms.php

Send TRAI-regulated transactional and service SMS in India with approved 6-character Headers and 19-digit Template IDs.

Parameters

Field	Type	Required	Description
channel	string	Optional	Set to `dlt_sms` (Default)
sender	string	Yes	6-character approved DLT Header (e.g. `CLOUDTX`)
mobile	string	Yes	10-digit Indian recipient mobile number (e.g. `9876543210`)
message	string	Yes	Message body matching approved template structure
dlt_template_id	string	Optional	19-digit registered DLT Content Template ID

JSON Success Response (200 OK)

{
  "status": "SUCCESS",
  "code": 200,
  "message_id": "DLT-20260907-A4B8C1",
  "channel": "dlt_sms",
  "recipient": "9876543210",
  "parts": 1,
  "cost": 0.2600,
  "delivery_status": "delivered",
  "remaining_balance": 2450.00
}

Integration SDK Snippets

curl -X POST "https://bulk5.com/api/v1/send_sms.php" \
  -H "Authorization: Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c" \
  -H "Content-Type: application/json" \
  -d '{
    "channel": "dlt_sms",
    "sender": "CLOUDTX",
    "mobile": "9876543210",
    "message": "Your OTP for verification is 482910. Valid for 10 mins. - Bulk5",
    "dlt_template_id": "1707161234567890123"
}'

<?php
$payload = array (
  'channel' => 'dlt_sms',
  'sender' => 'CLOUDTX',
  'mobile' => '9876543210',
  'message' => 'Your OTP for verification is 482910. Valid for 10 mins. - Bulk5',
  'dlt_template_id' => '1707161234567890123',
);

$ch = curl_init('https://bulk5.com/api/v1/send_sms.php');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POST => true,
    CURLOPT_HTTPHEADER => [
        'Authorization: Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c',
        'Content-Type: application/json'
    ],
    CURLOPT_POSTFIELDS => json_encode($payload)
]);
$response = curl_exec($ch);
curl_close($ch);
echo $response;

import requests

url = "https://bulk5.com/api/v1/send_sms.php"
headers = {
    "Authorization": "Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c",
    "Content-Type": "application/json"
}
payload = {
    "channel": "dlt_sms",
    "sender": "CLOUDTX",
    "mobile": "9876543210",
    "message": "Your OTP for verification is 482910. Valid for 10 mins. - Bulk5",
    "dlt_template_id": "1707161234567890123"
}
response = requests.post(url, json=payload, headers=headers)
print(response.status_code, response.json())

const response = await fetch("https://bulk5.com/api/v1/send_sms.php", {
  method: "POST",
  headers: {
    "Authorization": "Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "channel": "dlt_sms",
    "sender": "CLOUDTX",
    "mobile": "9876543210",
    "message": "Your OTP for verification is 482910. Valid for 10 mins. - Bulk5",
    "dlt_template_id": "1707161234567890123"
})
});

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

POST https://bulk5.com/api/v1/send_sms.php

Send high-capacity marketing campaigns. Automatically validates 10-digit Indian numbers and drops invalid entries without credit waste.

TRAI Regulatory Window (09:00 AM – 09:00 PM IST):

Promotional SMS can strictly be dispatched only between 09:00 AM and 09:00 PM Indian Standard Time. Requests outside this window return HTTP 400 with TRAI_PROMO_WINDOW_RESTRICTION.

Parameters

Field	Type	Required	Description
channel	string	Yes	Must be set to `promo_sms`
sender	string	Yes	Promotional Header or alphanumeric tag
mobile	string / array	Yes	10-digit mobile number or comma-separated list
message	string	Yes	Promotional campaign body text

JSON Success Response (200 OK)

{
  "status": "SUCCESS",
  "code": 200,
  "message_id": "PRM-20260907-9C3E1F",
  "channel": "promo_sms",
  "recipient": "9812345678",
  "parts": 1,
  "cost": 0.2200,
  "delivery_status": "delivered",
  "remaining_balance": 2450.00
}

Integration SDK Snippets

curl -X POST "https://bulk5.com/api/v1/send_sms.php" \
  -H "Authorization: Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c" \
  -H "Content-Type: application/json" \
  -d '{
    "channel": "promo_sms",
    "sender": "CLOUDTX",
    "mobile": "9812345678",
    "message": "Mega Weekend Offer! Enjoy 30% discount on all wholesale packages."
}'

<?php
$payload = array (
  'channel' => 'promo_sms',
  'sender' => 'CLOUDTX',
  'mobile' => '9812345678',
  'message' => 'Mega Weekend Offer! Enjoy 30% discount on all wholesale packages.',
);

$ch = curl_init('https://bulk5.com/api/v1/send_sms.php');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POST => true,
    CURLOPT_HTTPHEADER => [
        'Authorization: Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c',
        'Content-Type: application/json'
    ],
    CURLOPT_POSTFIELDS => json_encode($payload)
]);
$response = curl_exec($ch);
curl_close($ch);
echo $response;

import requests

url = "https://bulk5.com/api/v1/send_sms.php"
headers = {
    "Authorization": "Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c",
    "Content-Type": "application/json"
}
payload = {
    "channel": "promo_sms",
    "sender": "CLOUDTX",
    "mobile": "9812345678",
    "message": "Mega Weekend Offer! Enjoy 30% discount on all wholesale packages."
}
response = requests.post(url, json=payload, headers=headers)
print(response.status_code, response.json())

const response = await fetch("https://bulk5.com/api/v1/send_sms.php", {
  method: "POST",
  headers: {
    "Authorization": "Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "channel": "promo_sms",
    "sender": "CLOUDTX",
    "mobile": "9812345678",
    "message": "Mega Weekend Offer! Enjoy 30% discount on all wholesale packages."
})
});

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

POST https://bulk5.com/api/v1/send_sms.php

High-priority telecom queues engineered for 1-second OTP delivery. Dedicated low-latency routes.

Parameters

Field	Type	Required	Description
channel	string	Yes	Must be set to `otp_sms`
sender	string	Yes	Approved OTP Header
mobile	string	Yes	10-digit Indian recipient mobile
message	string	Yes	OTP notification message text

JSON Success Response (200 OK)

{
  "status": "SUCCESS",
  "code": 200,
  "message_id": "OTP-20260907-7E2A9B",
  "channel": "otp_sms",
  "recipient": "9876543210",
  "parts": 1,
  "cost": 0.2800,
  "delivery_status": "delivered",
  "latency_ms": 184,
  "remaining_balance": 2450.00
}

Integration SDK Snippets

curl -X POST "https://bulk5.com/api/v1/send_sms.php" \
  -H "Authorization: Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c" \
  -H "Content-Type: application/json" \
  -d '{
    "channel": "otp_sms",
    "sender": "CLOUDTX",
    "mobile": "9876543210",
    "message": "Your security code is 904312. Valid for 5 minutes."
}'

<?php
$payload = array (
  'channel' => 'otp_sms',
  'sender' => 'CLOUDTX',
  'mobile' => '9876543210',
  'message' => 'Your security code is 904312. Valid for 5 minutes.',
);

$ch = curl_init('https://bulk5.com/api/v1/send_sms.php');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POST => true,
    CURLOPT_HTTPHEADER => [
        'Authorization: Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c',
        'Content-Type: application/json'
    ],
    CURLOPT_POSTFIELDS => json_encode($payload)
]);
$response = curl_exec($ch);
curl_close($ch);
echo $response;

import requests

url = "https://bulk5.com/api/v1/send_sms.php"
headers = {
    "Authorization": "Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c",
    "Content-Type": "application/json"
}
payload = {
    "channel": "otp_sms",
    "sender": "CLOUDTX",
    "mobile": "9876543210",
    "message": "Your security code is 904312. Valid for 5 minutes."
}
response = requests.post(url, json=payload, headers=headers)
print(response.status_code, response.json())

const response = await fetch("https://bulk5.com/api/v1/send_sms.php", {
  method: "POST",
  headers: {
    "Authorization": "Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "channel": "otp_sms",
    "sender": "CLOUDTX",
    "mobile": "9876543210",
    "message": "Your security code is 904312. Valid for 5 minutes."
})
});

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

POST https://bulk5.com/api/v1/send_sms.php

Send verified Google Rich Communication Services (RCS) messages with rich media, brand logos, and action buttons.

Parameters

Field	Type	Required	Description
channel	string	Yes	Must be set to `rcs`
sender	string	Yes	Verified RCS Bot Name / ID
mobile	string	Yes	10-digit recipient mobile
message	string	Yes	RCS card text description
rcs_card_title	string	Optional	Headline for the rich card
rcs_button_url	string	Optional	URL for CTA action button
media_url	string	Optional	Image / Banner URL

JSON Success Response (200 OK)

{
  "status": "SUCCESS",
  "code": 200,
  "message_id": "RCS-20260907-5D4C3B",
  "channel": "rcs",
  "recipient": "9876543210",
  "parts": 1,
  "cost": 0.4500,
  "delivery_status": "delivered",
  "remaining_balance": 2450.00
}

Integration SDK Snippets

curl -X POST "https://bulk5.com/api/v1/send_sms.php" \
  -H "Authorization: Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c" \
  -H "Content-Type: application/json" \
  -d '{
    "channel": "rcs",
    "sender": "Bulk5Verified",
    "mobile": "9876543210",
    "message": "Unlock premium telecom wholesale rates with zero setup fees.",
    "rcs_card_title": "Exclusive Partner Invitation",
    "rcs_button_url": "https://bulk5.com/login.php",
    "media_url": "https://bulk5.com/bulk5.png"
}'

<?php
$payload = array (
  'channel' => 'rcs',
  'sender' => 'Bulk5Verified',
  'mobile' => '9876543210',
  'message' => 'Unlock premium telecom wholesale rates with zero setup fees.',
  'rcs_card_title' => 'Exclusive Partner Invitation',
  'rcs_button_url' => 'https://bulk5.com/login.php',
  'media_url' => 'https://bulk5.com/bulk5.png',
);

$ch = curl_init('https://bulk5.com/api/v1/send_sms.php');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POST => true,
    CURLOPT_HTTPHEADER => [
        'Authorization: Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c',
        'Content-Type: application/json'
    ],
    CURLOPT_POSTFIELDS => json_encode($payload)
]);
$response = curl_exec($ch);
curl_close($ch);
echo $response;

import requests

url = "https://bulk5.com/api/v1/send_sms.php"
headers = {
    "Authorization": "Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c",
    "Content-Type": "application/json"
}
payload = {
    "channel": "rcs",
    "sender": "Bulk5Verified",
    "mobile": "9876543210",
    "message": "Unlock premium telecom wholesale rates with zero setup fees.",
    "rcs_card_title": "Exclusive Partner Invitation",
    "rcs_button_url": "https:\/\/bulk5.com\/login.php",
    "media_url": "https:\/\/bulk5.com\/bulk5.png"
}
response = requests.post(url, json=payload, headers=headers)
print(response.status_code, response.json())

const response = await fetch("https://bulk5.com/api/v1/send_sms.php", {
  method: "POST",
  headers: {
    "Authorization": "Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "channel": "rcs",
    "sender": "Bulk5Verified",
    "mobile": "9876543210",
    "message": "Unlock premium telecom wholesale rates with zero setup fees.",
    "rcs_card_title": "Exclusive Partner Invitation",
    "rcs_button_url": "https:\/\/bulk5.com\/login.php",
    "media_url": "https:\/\/bulk5.com\/bulk5.png"
})
});

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

POST https://bulk5.com/api/v1/send_sms.php

Send Meta-verified WhatsApp Business template notifications, order updates, and marketing broadcasts.

Parameters

Field	Type	Required	Description
channel	string	Yes	Must be set to `whatsapp`
sender	string	Yes	WABA Phone Number ID
mobile	string	Yes	Recipient WhatsApp number with country code (e.g. `919876543210`)
message	string	Yes	Message body text
wa_template	string	Optional	Meta verified template identifier

JSON Success Response (200 OK)

{
  "status": "SUCCESS",
  "code": 200,
  "message_id": "WA-20260907-88B12A",
  "channel": "whatsapp",
  "recipient": "919876543210",
  "parts": 1,
  "cost": 0.6500,
  "delivery_status": "delivered",
  "remaining_balance": 2450.00
}

Integration SDK Snippets

curl -X POST "https://bulk5.com/api/v1/send_sms.php" \
  -H "Authorization: Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c" \
  -H "Content-Type: application/json" \
  -d '{
    "channel": "whatsapp",
    "sender": "918000111222",
    "mobile": "919876543210",
    "message": "Hello! Your order #9921 has been confirmed and is out for delivery.",
    "wa_template": "order_confirmation_v2",
    "media_url": "https://bulk5.com/bulk5.png"
}'

<?php
$payload = array (
  'channel' => 'whatsapp',
  'sender' => '918000111222',
  'mobile' => '919876543210',
  'message' => 'Hello! Your order #9921 has been confirmed and is out for delivery.',
  'wa_template' => 'order_confirmation_v2',
  'media_url' => 'https://bulk5.com/bulk5.png',
);

$ch = curl_init('https://bulk5.com/api/v1/send_sms.php');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POST => true,
    CURLOPT_HTTPHEADER => [
        'Authorization: Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c',
        'Content-Type: application/json'
    ],
    CURLOPT_POSTFIELDS => json_encode($payload)
]);
$response = curl_exec($ch);
curl_close($ch);
echo $response;

import requests

url = "https://bulk5.com/api/v1/send_sms.php"
headers = {
    "Authorization": "Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c",
    "Content-Type": "application/json"
}
payload = {
    "channel": "whatsapp",
    "sender": "918000111222",
    "mobile": "919876543210",
    "message": "Hello! Your order #9921 has been confirmed and is out for delivery.",
    "wa_template": "order_confirmation_v2",
    "media_url": "https:\/\/bulk5.com\/bulk5.png"
}
response = requests.post(url, json=payload, headers=headers)
print(response.status_code, response.json())

const response = await fetch("https://bulk5.com/api/v1/send_sms.php", {
  method: "POST",
  headers: {
    "Authorization": "Bearer sec_live_9f8a2b3c4d5e6f7a8b9c0d1e2f3a4b5c",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "channel": "whatsapp",
    "sender": "918000111222",
    "mobile": "919876543210",
    "message": "Hello! Your order #9921 has been confirmed and is out for delivery.",
    "wa_template": "order_confirmation_v2",
    "media_url": "https:\/\/bulk5.com\/bulk5.png"
})
});

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

Developer API Reference & SDKs

Sub-Second SLA

100% DLT Compliant

5 Unified Channels

Bearer Token Auth

Parameters

JSON Success Response (200 OK)

Integration SDK Snippets

Parameters

JSON Success Response (200 OK)

Integration SDK Snippets

Parameters

JSON Success Response (200 OK)

Integration SDK Snippets

Parameters

JSON Success Response (200 OK)

Integration SDK Snippets

Parameters

JSON Success Response (200 OK)

Integration SDK Snippets

JSON Success Response (200 OK)

cURL Example

JSON Success Response (200 OK)

cURL DLR Query