Overview

Money In Operation — Funds are transferred from the customer’s card to your SingaPay Payment Gateway account.

API Overview

API Version

v2.0

Base Path

/api/v2.0/card

Authentication

Bearer Token (JWT, OAuth 2.0 client credentials)

Content-Type

application/json

Authentication

Merchants must obtain a JWT access token before calling Card endpoints. See Authentication for token requests, required headers, and IP whitelist setup.

Base URL

Environment	Base URL
Production	`https://{your-domain}/api/v2.0/card`
Staging / Local	`https://{your-domain}/api/v2.0/card`

Card Payment Flow

Transaction Status Lifecycle

pending

Awaiting 3DS (includes internal pre-submission state).

processing

Payment submitted, awaiting final result.

success

Payment completed successfully.

failed

Payment failed (issuer declined or error).

cancelled

Voided — transaction was not captured.

refunded

Refunded after capture.

Path Parameters

Parameter	Description
`{account_id}`	Merchant Account ULID — e.g. `01K5G4FZZ18DMK0M5QTR8Y9QY9`
`{id}`	Transaction ID (format: `99` + ULID, 28 chars) — e.g. `9901JAB3CD4E5F6G7H8J9K0`

Available Endpoints

Payment (One-Time)

Process a one-time card payment (full or installment) in a single request with amount, customer info, and card data.

Cancel Transaction

Void or refund a transaction depending on its current status.

Inquiry Status

Check the latest transaction status and optionally update the local record.

Error Responses

HTTP Status Codes

Code	Description
`200`	Success
`400`	Bad Request (validation or business rule error)
`401`	Unauthorized (invalid or missing token)
`404`	Account or resource not found
`422`	Validation error
`500`	Internal server error

Standard Error Format

All API responses follow the v2 format with response_code and response_message:

{
  "response_code": "SP001",
  "response_message": "Human-readable error message",
  "data": {
    "transaction_id": "9901JAB3CD4E5F6G7H8J9K0M1N2"
  }
}

Response Codes

Code	Description	HTTP Status
`SP000`	Success	200
`SP001`	Transaction Failure (issuer declined)	400
`SP002`	General Failure (internal error)	500
`SP009`	Transaction Not Found	404
`SP012`	Bad Request (invalid status, validation)	400
`SP020`	Merchant Account Not Found	404

Appendix

Installment Type Reference

Value	Description
`1`	Full payment
`2`	Installment

Installment Month Options

Value	Description
`1`	1 month
`3`	3 months
`6`	6 months
`12`	12 months

Transaction ID Format

Channel	Format	Example
Card	`99` + ULID (28 chars)	`9901JAB3CD4E5F6G7H8J9K0M1N2`
E-Wallet	`88` + ULID	`8801JAB3CD4E5F6G7H8J9K0M1N2`
QRIS	`66` + ULID	`6601JAB3CD4E5F6G7H8J9K0M1N2`

Important Notes

Single-Step Payment

Card payments are processed in a single API call that includes amount, customer info, and card data together — no pre-registration step required.

3DS Authentication

When the issuing bank requires 3DS, the payment response includes a payment_url or html_form field. Render this for the customer to complete authentication before the transaction finalises.

Cancellation (Void vs Refund)

Transactions can be voided (before capture) or refunded (after capture) using the Cancel endpoint. Both return status: "success" — use the cancel_type field to distinguish which occurred.

IP Whitelisting

Merchant API routes require IP whitelisting. Ensure your server IP is registered under the merchant account before going live.

Installment Payments

Supports full payment and installment options (1, 3, 6, or 12 months) via the installment and installment_month request parameters.

Changelog

Date	Description
2026-02-25	Initial documentation
2026-02-25	Transaction reference kept internal; removed from API responses
2026-02-25	`transaction_id` format aligned with VA/E-Wallet (TransactionCode + ULID)
2026-02-26	Migrated to v2 response format (`response_code`/`response_message`), added error logging
2026-02-26	Refactored to single-step one-time payment; removed `register-transaction`; request uses `card_number`, `card_expiry`, `card_cvv`, `card_holder_name`

Getting Started

Security

Accept Money

Send Money

Transaction Records

Money Accounts

Webhook

API Overview

API Version

Base Path

Authentication

Content-Type

Authentication

Base URL

Card Payment Flow

Transaction Status Lifecycle

Path Parameters

Available Endpoints

Payment (One-Time)

Cancel Transaction

Inquiry Status

Error Responses

HTTP Status Codes

Standard Error Format

Response Codes

Appendix

Installment Type Reference

Installment Month Options

Transaction ID Format

Important Notes

Changelog

​API Overview

API Version

Base Path

Authentication

Content-Type

​Authentication

​Base URL

​Card Payment Flow

​Transaction Status Lifecycle

​Path Parameters

​Available Endpoints

Payment (One-Time)

Cancel Transaction

Inquiry Status

​Error Responses

​HTTP Status Codes

​Standard Error Format

​Response Codes

​Appendix

​Installment Type Reference

​Installment Month Options

​Transaction ID Format

​Important Notes

​Changelog

API Overview

Authentication

Base URL

Card Payment Flow

Transaction Status Lifecycle

Path Parameters

Available Endpoints

Error Responses

HTTP Status Codes

Standard Error Format

Response Codes

Appendix

Installment Type Reference

Installment Month Options

Transaction ID Format

Important Notes

Changelog