Invoicing

Introduction

In this type of integration, we are providing a simple, straightforward integration. It will allow you to generate an invoice link that can be sent by any channel we support.

This will facilitate your collection if you have non-store platforms and would like to introduce a niche to your business. You can decide how are you going to send the payment link either by SMS, email, redirect the customer to the invoice link, or use all of them.

This is so helpful in many business cases. Let's explain an example of such cases that can utilize this integration. In a rent collection case, all you need is to give your customers an invoice link to pay the due rent at their convenience. This simply can be achieved with this type of integration, based on the due dates of the collection, and within your application, you can call this endpoint and send all information and the amount you need to collect, then nstFi will send this payment link via the provided channel. The thing here is that you are giving time to your customers to pay once they can.

How It Works

Step 1: Create a Payment Request

To generate an invoice, send a POST request to the endpoint: POST /v3/payments (Create Payment)

In this request, you don’t need to set the PaymentMethod value. Just specify how the customer should receive the invoice link using the NotificationOption field.

NotificationOption Values

{
  "Order": {
    "Amount": 20
  },
  "Customer": {
    "Mobile": {
      "CountryCode": "+20",
      "Number": "1020304050"
    },
    "Email": "[email protected]"
  },
  "IntegrationUrls": {
    "Redirection": "https://your-website.com/payment-callback"
  },
  "NotificationOption": "ALL"
}

{
  "IsSuccess": true,
  "Message": "",
  "ValidationErrors": null,
  "Data": {
    "InvoiceId": "6323179",
    "PaymentId": null,
    "PaymentURL": "https://demo.nstFi.com/KWT/ie/01072632317941-057d0668",
    "PaymentCompleted": false,
    "TransactionDetails": null
  }
}

Step 2: Inquire Payment Status

After the customer completes the payment, nstFi will redirect the user back to your Redirection URL, appending a paymentId query parameter.

Example: https://your-website.com/payment-callback?paymentId=100201923790872553

You need then call: GET /v3/payments/{paymentId} (Get Payment Details) to verify the payment and retrieve the full invoice and transaction details.

GET /v3/payments/07076323179317752773

{
    "IsSuccess": true,
    "Message": "",
    "ValidationErrors": null,
    "Data": {
        "Invoice": {
            "Id": "6389491",
            "Status": "PAID",
            "Reference": "2025060917",
            "CreationDate": "2025-12-24T14:48:17.1230000Z",
            "ExpirationDate": "2026-06-22T14:48:17.1230000Z",
            "ExternalIdentifier": null,
            "UserDefinedField": "",
            "MetaData": null
        },
        "Transaction": {
            "Id": "102585",
            "Status": "SUCCESS",
            "PaymentMethod": "VISA/MASTER",
            "PaymentId": "07076389491322460173",
            "ReferenceId": "535814102585",
            "TrackId": "24-12-2025_3224601",
            "AuthorizationId": "102585",
            "TransactionDate": "2025-12-24T14:51:06.5630000Z",
            "ECI": "02",
            "IP": {
                "Address": "41.35.105.183",
                "Country": "Egypt"
            },
            "Error": {
                "Code": "",
                "Message": ""
            },
            "Card": {
                "NameOnCard": "das",
                "Number": "512345xxxxxx0008",
                "Token": "",
                "PanHash": "b888aa5f23a817883d4d12c74044bab1ae6ee65dc8d6e11515394aba452b273b",
                "ExpiryMonth": "12",
                "ExpiryYear": "34",
                "Brand": "Mastercard",
                "Issuer": "Test Bank",
                "IssuerCountry": "KWT",
                "FundingMethod": "credit"
            }
        },
        "Customer": {
            "Reference": "",
            "Name": "Anonymous",
            "Mobile": "+201020304050",
            "Email": "[email protected]"
        },
        "Amount": {
            "BaseCurrency": "KWD",
            "ValueInBaseCurrency": "20",
            "ServiceCharge": "0.4",
            "ServiceChargeVAT": "0.06",
            "ReceivableAmount": "19.54",
            "DisplayCurrency": "KWD",
            "ValueInDisplayCurrency": "20",
            "PayCurrency": "KWD",
            "ValueInPayCurrency": "20"
        },
        "Suppliers": []
    }
}

👍 Webhook

We recommended enabling the Webhook feature to automatically notify your system when a transaction status changes in your application.

📘 Note

The IntegrationUrls.Redirection field is optional. If omitted, customers will remain on the nstFi result page after completing payment.

📘 Old Integration (V2)

In case you are using the integration for v2, you can find the documentation here:

• Invoice Link
• SendPayment
• Sample Code