Complete Merchant Onboarding with Gcashier Pay API

Merchant onboarding with Gcashier Pay is a fully API-driven KYC process. You submit your business details and supporting documents through the sp1101 endpoint, Gcashier Pay’s compliance team reviews the application, and the result — including your live merchant token — is delivered to your server via the sp3101 webhook. If your application requires supplementary materials, you’ll receive a 80000 callback code prompting you to upload them. Once approved, you can modify your registration at any time using sp1102.

Overview

Submit merchant access application (sp1101)

Send your KYC details, business information, and document URLs.

Receive the onboarding result (sp3101 webhook)

Gcashier Pay posts the review outcome — and your token — to your callback URL.

Handle additional material requests (code 80000)

If compliance needs more documents, re-submit via the reMaterial field.

Modify your application if needed (sp1102)

Update any registered fields before or after approval.

Step 1 — Submit the Merchant Access Application

Call POST /api/sp1101 with your business profile, document URLs, and callback endpoint. The table below describes the key request fields.

Field	Required	Description
`merOrderNo`	M	Your unique order reference for this application
`email`	M	Business contact email
`phoneAreaCode` / `phoneNum`	M	Contact phone with country prefix
`countryCode`	M	ISO country code of the business
`merNameEn`	M	Merchant name in English
`merNameCn`	O	Merchant name in Chinese (optional)
`parentRemark`	M	Whether this is a sub-merchant: `0` = No, `1` = Yes
`addressType`	M	`0` = Self-Rented, `1` = Secretariat, `2` = Shared
`businessMainActors`	M	`0` = Company, `1` = Individual
`lastYearTurnover`	M	Turnover band 0–5
`estimatedTradingVolume`	M	Estimated volume band 0–5
`riskCountryTransaction`	M	Whether the merchant transacts with risk-listed countries
`certificate`	M	`List<String>` of business certificate document URLs
`customerIdentity`	M	`List<String>` of identity document URLs
`customerId`	M	`List<personInfo>` — customer identity detail objects
`shareholder`	M	`List<personInfo>` — shareholder identity detail objects
`authorization`	M	`List<String>` of authorization document URLs
`sourceFunds`	M	`List<String>` of fund source evidence URLs
`paymentPurpose`	M	`List<String>` of payment purpose document URLs
`clientCountry`	M	`List<String>` of countries where clients are based
`businessNature`	M	Object with `natureType` and `natures` describing your business
`callbackUrl`	M	Your HTTPS endpoint for the sp3101 webhook
`noticeMarker`	M	Notification preference marker
`certificateNo`	M	Business registration / certificate number
`processVersion`	O	Process version identifier (leave blank for default)

All document fields accept HTTPS URLs pointing to pre-uploaded files. Ensure each URL is publicly accessible by Gcashier Pay’s servers at review time. Files must be in PDF, JPG, or PNG format and must not exceed 10 MB each.

Request Example

{
  "merOrderNo": "MER20240601001",
  "email": "compliance@acme-trade.com",
  "phoneAreaCode": "65",
  "phoneNum": "81234567",
  "referralChannel": "PARTNER_PORTAL",
  "countryCode": "SG",
  "merNameEn": "Acme Trade Pte Ltd",
  "merNameCn": "艾克米贸易有限公司",
  "payerCity": "Singapore",
  "parentRemark": "0",
  "branchRemark": "HQ",
  "addressType": "0",
  "realCompanyAddress": "80 Robinson Road, #08-01, Singapore 068898",
  "businessMainActors": "0",
  "lastYearTurnover": "3",
  "estimatedTradingVolume": "2",
  "riskCountryTransaction": "N",
  "certificateNo": "202400123G",
  "noticeMarker": "1",
  "certificate": [
    "https://docs.acme-trade.com/kyc/bizreg.pdf"
  ],
  "customerIdentity": [
    "https://docs.acme-trade.com/kyc/id_front.jpg",
    "https://docs.acme-trade.com/kyc/id_back.jpg"
  ],
  "customerId": [
    {
      "name": "Jane Doe",
      "idType": "PASSPORT",
      "idNo": "E12345678",
      "nationality": "SG"
    }
  ],
  "shareholder": [
    {
      "name": "John Smith",
      "idType": "PASSPORT",
      "idNo": "A98765432",
      "nationality": "GB",
      "shareholdingRatio": "60"
    }
  ],
  "authorization": [
    "https://docs.acme-trade.com/kyc/authorization_letter.pdf"
  ],
  "sourceFunds": [
    "https://docs.acme-trade.com/kyc/bank_statement_q1.pdf"
  ],
  "paymentPurpose": [
    "https://docs.acme-trade.com/kyc/payment_purpose.pdf"
  ],
  "clientCountry": ["SG", "MY", "ID"],
  "businessNature": {
    "natureType": "ECOMMERCE",
    "natures": ["Retail", "Cross-border goods"]
  },
  "callbackUrl": "https://api.acme-trade.com/webhooks/gcashier/onboarding"
}

{
  "bizFlow": "BF20240601000123",
  "merOrderNo": "MER20240601001",
  "status": "ACCEPT",
  "code": "S00001",
  "message": "Application received and under review."
}

A status of ACCEPT and code of S00001 means Gcashier Pay has accepted your submission for review. Store bizFlow — you’ll need it to track progress and for any subsequent modification requests.

Step 2 — Receive the Onboarding Result Webhook (sp3101)

When the compliance review is complete, Gcashier Pay posts a JSON payload to the callbackUrl you specified. On success, the payload includes your permanent token, which you must include in the Authorization header of all subsequent API calls.

Webhook Payload

{
  "bizFlow": "BF20240601000123",
  "merOrderNo": "MER20240601001",
  "code": "S00000",
  "message": "Merchant access approved.",
  "merchantNo": "MCH0000456",
  "merNameEn": "Acme Trade Pte Ltd",
  "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJtZXJjaGFudE5vIjoiTUNIMDAwMDQ1NiJ9.signature"
}

{
  "bizFlow": "BF20240601000123",
  "merOrderNo": "MER20240601001",
  "code": "S00002",
  "message": "Application rejected: insufficient identity documentation.",
  "merchantNo": "",
  "merNameEn": "Acme Trade Pte Ltd",
  "token": ""
}

Store your token securely — treat it like an API secret key. Rotate it immediately if you suspect it has been compromised by contacting Gcashier Pay support.

Code	Meaning
`S00000`	Application approved; `token` is populated
`S00002`	Application rejected; review the `message` for reasons
`80000`	Additional materials required (see below)

Step 3 — Handle Additional Material Requests (Code 80000)

If the webhook delivers code: "80000", compliance has reviewed your application but requires supplementary documentation before approval. The response body will include a reMaterial field listing the specific document types needed.

When you receive a 80000 callback, your bizFlow remains active. You do not need to submit a new sp1101 request — instead, call sp1102 with the same bizFlow and attach the requested materials.

How to respond:

Inspect the reMaterial array to identify which document categories are required.
Upload the new files and obtain fresh HTTPS URLs.
Call POST /api/sp1102 with your bizFlow and the updated document fields (see Step 4).

Step 4 — Modify Merchant Access (sp1102)

Use POST /api/sp1102 to update your application at any stage — whether responding to a 80000 request or correcting details after approval.

{
  "bizFlow": "BF20240601000123",
  "sourceFunds": [
    "https://docs.acme-trade.com/kyc/bank_statement_q2.pdf",
    "https://docs.acme-trade.com/kyc/audited_accounts_2023.pdf"
  ],
  "paymentPurpose": [
    "https://docs.acme-trade.com/kyc/updated_payment_purpose.pdf"
  ]
}

{
  "bizFlow": "BF20240601000123",
  "status": "ACCEPT",
  "code": "S00001",
  "message": "Modification received and under review."
}

Only include the fields you need to change in the sp1102 request body. All other registered fields remain unchanged.

Test Environment Behaviour

In the Gcashier Pay sandbox, you can simulate different review outcomes by controlling the last digit of your merOrderNo:

Last digit of `merOrderNo`	Simulated outcome
`0` – `3`	Approved — `S00000` webhook delivered with test token
`4` – `6`	Rejected — `S00002` webhook delivered
`7` – `9`	Additional materials requested — `80000` webhook delivered

Start sandbox testing with a merOrderNo ending in 1 to get an instant approval and a test token you can use for all downstream API calls.

Getting Started

Core Concepts

Guides

Complete Merchant Onboarding with Gcashier Pay API

Overview

Step 1 — Submit the Merchant Access Application

Request Example

Step 2 — Receive the Onboarding Result Webhook (sp3101)

Webhook Payload

Step 3 — Handle Additional Material Requests (Code 80000)

Step 4 — Modify Merchant Access (sp1102)

Test Environment Behaviour

​Overview

​Step 1 — Submit the Merchant Access Application

​Request Example

​Step 2 — Receive the Onboarding Result Webhook (sp3101)

​Webhook Payload

​Step 3 — Handle Additional Material Requests (Code 80000)

​Step 4 — Modify Merchant Access (sp1102)

​Test Environment Behaviour

Overview

Step 1 — Submit the Merchant Access Application

Request Example

Step 2 — Receive the Onboarding Result Webhook (sp3101)

Webhook Payload

Step 3 — Handle Additional Material Requests (Code 80000)

Step 4 — Modify Merchant Access (sp1102)

Test Environment Behaviour