Paydios Merchant ID: Find and Use It

Your Merchant ID is the unique identifier for your Paydios merchant account. You need it in the URL path of certain API calls — specifically when creating and verifying checkout sessions. Unlike your API keys, the Merchant ID is not a secret and does not need to be hidden from logs or version control.

Where to find your Merchant ID

Log in to the Paydios dashboard and navigate to Dashboard → API Keys. Your Merchant ID appears at the top of the page, above your API keys, in the format:

mid_xxxxxxxxxxxxxxxx

Copy it and store it alongside your other environment configuration.

Using your Merchant ID in API requests

Two API endpoints require your Merchant ID in the URL path:

Method	Endpoint	Purpose
`POST`	`/merchant-api/{merchant_id}/checkout-sessions`	Create a checkout session
`GET`	`/merchant-api/{merchant_id}/{session_id}`	Retrieve or verify a session

Replace {merchant_id} with your actual Merchant ID value. You still need to include your secret key as a Bearer token in the Authorization header.

Create a checkout session

curl -X POST https://api.paydios.io/merchant-api/mid_xxxxxxxxxxxxxxxx/checkout-sessions \
  -H "Authorization: Bearer sk_live_xxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "amount": 2999,
    "currency": "USD",
    "description": "Order #1042",
    "source": "custom_php"
  }'

Verify a checkout session

curl https://api.paydios.io/merchant-api/mid_xxxxxxxxxxxxxxxx/sess_xxxxxxxxxx \
  -H "Authorization: Bearer sk_live_xxxxxxxxx"

Using your Merchant ID with the PHP SDK

The PHP SDK accepts your Merchant ID as an argument when calling session methods — you do not need to embed it in a URL manually.

<?php

require __DIR__ . '/vendor/autoload.php';

use Paydios\Client;

$pk = new Client(); // reads PAYDIOS_SECRET_KEY from .env automatically

$merchantId = 'mid_xxxxxxxxxxxxxxxx';

// Create a checkout session
$session = $pk->sessions()->create($merchantId, [
    'amount'      => 2999,
    'currency'    => 'USD',
    'description' => 'Order #1042',
    'source'      => 'custom_php',
]);

$sessionId = $session['session_id'];

// Verify the session after the customer returns
$status = $pk->sessions()->verify($merchantId, $sessionId);

echo $status['status']; // e.g. "paid"

Store your Merchant ID in an environment variable alongside your secret key so both are available to your application at runtime without being hard-coded.

PAYDIOS_SECRET_KEY=sk_live_xxxxxxxxx
PAYDIOS_MERCHANT_ID=mid_xxxxxxxxxxxxxxxx

Merchant ID vs. API keys

Credential	Purpose	Keep secret?
Merchant ID	Identifies your account in URL paths	No — safe to log and reference
Secret Key (`sk_live_…`)	Authenticates all API requests	Yes — treat like a password
Publishable Key	Client-side checkout operations	No — safe for browser code

Your Merchant ID does not change. You do not need to rotate it. If you believe your account has been compromised, rotate your API keys (not your Merchant ID) from the dashboard.

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Core Features

Merchant Account

Integrations

Platform & Security

Paydios Merchant ID: Find and Use It

Where to find your Merchant ID

Using your Merchant ID in API requests

Create a checkout session

Verify a checkout session

Using your Merchant ID with the PHP SDK

Merchant ID vs. API keys

​Where to find your Merchant ID

​Using your Merchant ID in API requests

​Create a checkout session

​Verify a checkout session

​Using your Merchant ID with the PHP SDK

​Merchant ID vs. API keys

Where to find your Merchant ID

Using your Merchant ID in API requests

Create a checkout session

Verify a checkout session

Using your Merchant ID with the PHP SDK

Merchant ID vs. API keys