Omni API

Refund

POST /transactions/refund
Api key header

Process a referenced refund or void for a previously completed sale or capture transaction. If the transaction is in the current batch, the system will attempt to void it, otherwise it will be refunded resulting in a financial transaction.

Webhook Events

The following webhook events will be triggered during the refund process:

  • refund.completed - when a transaction void or refund for a previously completed transaction is completed.
application/json

Body object Required

The request to refund or void a previously completed transaction.

One of:
Refund using Transaction ID object Refund using Reference ID object

Responses

  • 200 application/json

    A successful refund response

    Hide response attributes Show response attributes object
    • id string

      Unique ID for this refund transaction.

    • timestamp string(date-time)

      Transaction timestamp in UTC

    • type string

      Type of transaction

      Values are Sale, Auth, Capture, Refund, or Void.

    • status string

      The current status of the transaction

      Values are Created, Completed, or Pending.

    • paymentMethod object

      The payment method used for this transaction.

      Hide paymentMethod attributes Show paymentMethod attributes object
      • id string Required

        The unique identifier of the payment method. This ID has a prefix that makes it human-readable (pmt_trm_* for physical terminals, pmt_vrt_* for virtual terminals, pmt_tkn_* for tokenized cards), but applications should always use the type field to determine the payment method type rather than parsing this ID.

      • dateDeleted string(date-time)

        The date and time (UTC) when this payment method token was removed from the system using the Remove Token endpoint. This parameter will only be returned if the token was removed/deleted from the system.

        This field will be present in three scenarios:

        • As part of a successful Remove Token endpoint response
        • In token.removed webhook notifications
        • In List Transactions responses for transactions where the associated token was later removed

        When this field is present, sensitive card details (maskedCardNumber, cardExpDate) will be removed for security purposes, but all other transaction data remains intact.

      • type string Required

        The type of payment method:

        • Physical - A physical payment terminal for Card Present transactions
        • Virtual - A hosted payment form/iframe for Card Not Present transactions
        • Token - A tokenized card for card-on-file transactions

        Values are Physical, Virtual, or Token.

      • currency string Required

        The currency of the payment method.

        Values are USD or CAD.

      • description string

        A human-readable name for the payment method.

      • cardType string

        The type of card used for this transaction:

        • UNKNOWN - The card type is unknown
        • DEBIT - Debit Card
        • VISA - Visa Credit Card
        • MASTERCARD - MasterCard Credit Card
        • AMEX - American Express Credit Card
        • DINERS - Diners Club Credit Card
        • DISCOVER - Discover Credit Card
        • JCB - JCB Credit Card
        • UNIONPAY - UnionPay Credit Card
        • MAESTRO - Maestro Debit Card
        • GIFT - Gift Card
        • CASH - All-cash Transaction
        • EBT - Electronic Benefits Transfer Card
        • OTHER - Other tender types

        Values are UNKNOWN, DEBIT, VISA, MASTERCARD, AMEX, DINERS, DISCOVER, JCB, UNIONPAY, MAESTRO, GIFT, CASH, EBT, or OTHER.

      • maskedCardNumber string

        The masked card number. The format may vary (e.g. *********0011, 4*0011, etc.)

      • cardExpDate string

        The expiration date of the card in MMYY format.

    • invoiceNumber string

      An optional alphanumeric invoice number for this transaction. If provided in the request, the same value will be populated in the response.

      Maximum length is 100.

    • orderNumber string

      An optional alphanumeric order number for this transaction. If provided, the same value will be populated in the response.

      Maximum length is 100.

    • referenceId string

      The reference ID for this transaction. This will either be the reference ID provided in the transaction request or, if no value was provided, a value generated automatically by the system. This reference ID can be used for processing captures and referenced refunds by including it in the originalReferenceId field of subsequent transactions.

      Maximum length is 100.

    • resultCode number

      Result codes:

      • 0 - Successful transaction request. (Check each transactionResponse's responseCode to determine if a transaction was approved or declined, card was tokenized, etc.)
      • 1003 - The payment terminal is busy or unavailable. (If this error persists, the user may need to close and re-open the Payment Application on the terminal or restart the terminal)
      • 1005 - The specified terminal could not be found.
      • 3000 - An unexpected error occurred. Please try again.
      • 3002 - The transaction could not be completed because the payment terminal could not find the related transaction.
      • 3005 - To resolve this error, power off your payment terminal, wait one minute and retry the transaction. If the error persists, please contact support.
      • 3006 - The transaction could not be completed because the payment terminal is low on battery.
      • 3009 - The transaction could not be completed because of network connectivity issues with the payment terminal. Please restore connectivity and try again.
      • 3010 - The transaction took too long and was cancelled by the application.
      • 3011 - Invalid transaction request. Please consult the documentation for valid transaction requests.
      • 3012 - Invalid transaction request. paymentMethodId is invalid.
      • 3013 - Invalid transaction request. The specified amount appears to be incorrect. Please retry with a smaller amount.
      • 3014 - Invalid amount. Please try your transaction again with an amount greater than $0.
      • 3020 - An unsupported transaction result was received.
      • 9998 - The system is not ready to process a transaction.
      • 9999 - An unknown error has occurred. If available, an auxiliary error code will be provided in the message.

      Values are 0, 1003, 1005, 3000, 3002, 3005, 3006, 3009, 3010, 3011, 3012, 3013, 3014, 3020, 9998, or 9999.

    • resultText string

      A message describing the result code in more detail.

    • requestedAmount number

      The amount requested for refund. If not specified in the request, this will be the full transaction amount.

    • approvedAmount number

      The amount that was successfully refunded or voided.

    • transactionResponses array[object]

      A list of all transaction responses received during the refund. In most cases, there will be only one response.

      A single Sale Transaction may result in multiple Responses.

      Hide transactionResponses attributes Show transactionResponses attributes object
      • responseCode number

        Response codes:

        • 0 - UNKNOWN
        • 1 - APPROVED - Transaction was approved
        • 2 - PARTIAL_APPROVED - Transaction was partially approved, but not for the full requested amount.
        • 10 - DECLINED - Transaction was declined by the issuer or bank. For Card-Present, the transaction can also be declined offline by the terminal.
        • 11 - INSUFFICIENT_FUNDS - Rejected due to insufficient funds in the account.
        • 12 - CARD_EXPIRED - The card used for the transaction has expired.
        • 13 - FRAUD_SUSPECTED - The transaction was flagged for potential fraud.
        • 14 - INVALID_PAYMENT_INFO - The provided information is invalid (e.g.: card number).
        • 15 - LIMIT_EXCEEDED - Rejected due to reaching a limit (e.g.: credit limit).
        • 16 - VERIFICATION_REQUIRED - Additional customer verification is required for the transaction to proceed (e.g.: 3D Secure).
        • 17 - AUTHENTICATION_FAILED - Rejected due to incorrect PIN or authentication failure.
        • 18 - POLICY_VIOLATION - Rejected due to a violation of the payment gateway's terms of service or policies.
        • 19 - BATCH_EMPTY - Indicates that the batch for processing is empty.
        • 20 - RECORD_NOT_FOUND - Indicates that the requested record for a transaction was not found (e.g.: to VOID a reference).
        • 21 - ALREADY_VOIDED - Indicates that the transaction has already been voided and cannot be processed again.
        • 50 - NETWORK_ERROR - Rejected due to network or communication issues with the payment gateway.
        • 51 - INVALID_ECR_PARAMETER - Payment Terminal or system-specific errors.
        • 52 - NOT_SUPPORTED - Rejected because the requested operation is not supported.
        • 53 - BUSY_OR_UNAVAILABLE - The Payment Terminal, Payment App or system is busy or unavailable.
        • 54 - CANCELLED - Cancelled by the user or merchant.
        • 55 - USER_CANCELLED - Specific to scenarios where the user cancels the transaction.
        • 56 - TIMED_OUT_ON_USER_INPUT - Failed to complete the transaction in time.

        Values are 0, 1, 2, 10, 11, 14, 15, 16, 17, 18, 19, 20, 21, 50, 51, 52, 53, 54, 55, or 56.

      • authCode string

        The authorization code provided by the card issuer, confirming transaction approval.

      • amountApproved number

        The amount approved for this transaction response.

      • approvedAmountBreakdown object

        A breakdown of approvedAmount, where each amounts approved on the payment terminal are returned separately.

        Hide approvedAmountBreakdown attributes Show approvedAmountBreakdown attributes object
        • amountGoodsAndServices number

          The approved amount for goods and services.

        • tax number

          The approved tax amount.

        • cashback number

          The approved cashback amount.

        • tip number

          The approved tip amount.

      • paymentMethod object

        The payment method used for this transaction.

        Hide paymentMethod attributes Show paymentMethod attributes object
        • id string Required

          The unique identifier of the payment method. This ID has a prefix that makes it human-readable (pmt_trm_* for physical terminals, pmt_vrt_* for virtual terminals, pmt_tkn_* for tokenized cards), but applications should always use the type field to determine the payment method type rather than parsing this ID.

        • dateDeleted string(date-time)

          The date and time (UTC) when this payment method token was removed from the system using the Remove Token endpoint. This parameter will only be returned if the token was removed/deleted from the system.

          This field will be present in three scenarios:

          • As part of a successful Remove Token endpoint response
          • In token.removed webhook notifications
          • In List Transactions responses for transactions where the associated token was later removed

          When this field is present, sensitive card details (maskedCardNumber, cardExpDate) will be removed for security purposes, but all other transaction data remains intact.

        • type string Required

          The type of payment method:

          • Physical - A physical payment terminal for Card Present transactions
          • Virtual - A hosted payment form/iframe for Card Not Present transactions
          • Token - A tokenized card for card-on-file transactions

          Values are Physical, Virtual, or Token.

        • currency string Required

          The currency of the payment method.

          Values are USD or CAD.

        • description string

          A human-readable name for the payment method.

        • cardType string

          The type of card used for this transaction:

          • UNKNOWN - The card type is unknown
          • DEBIT - Debit Card
          • VISA - Visa Credit Card
          • MASTERCARD - MasterCard Credit Card
          • AMEX - American Express Credit Card
          • DINERS - Diners Club Credit Card
          • DISCOVER - Discover Credit Card
          • JCB - JCB Credit Card
          • UNIONPAY - UnionPay Credit Card
          • MAESTRO - Maestro Debit Card
          • GIFT - Gift Card
          • CASH - All-cash Transaction
          • EBT - Electronic Benefits Transfer Card
          • OTHER - Other tender types

          Values are UNKNOWN, DEBIT, VISA, MASTERCARD, AMEX, DINERS, DISCOVER, JCB, UNIONPAY, MAESTRO, GIFT, CASH, EBT, or OTHER.

        • maskedCardNumber string

          The masked card number. The format may vary (e.g. *********0011, 4*0011, etc.)

        • cardExpDate string

          The expiration date of the card in MMYY format.

      • cardType string

        The type of card used for this transaction:

        • UNKNOWN - The card type is unknown
        • DEBIT - Debit Card
        • VISA - Visa Credit Card
        • MASTERCARD - MasterCard Credit Card
        • AMEX - American Express Credit Card
        • DINERS - Diners Club Credit Card
        • DISCOVER - Discover Credit Card
        • JCB - JCB Credit Card
        • UNIONPAY - UnionPay Credit Card
        • MAESTRO - Maestro Debit Card
        • GIFT - Gift Card
        • CASH - All-cash Transaction
        • EBT - Electronic Benefits Transfer Card
        • OTHER - Other tender types

        Values are UNKNOWN, DEBIT, VISA, MASTERCARD, AMEX, DINERS, DISCOVER, JCB, UNIONPAY, MAESTRO, GIFT, CASH, EBT, or OTHER.

      • avsResult string

        The AVS (Address Verification Service) result. Typically returned on Card Not Present transactions.

        • A - Address matches, ZIP does not. The first five numerical characters contained in the address match those stored at the VIC or issuer's center. However, the ZIP code does not match.
        • E - Ineligible transaction.
        • N - Neither address nor ZIP matches. Neither the first five numerical characters contained in the address match with those stored at the VIC nor issuer's center nor the ZIP code match.
        • R - Retry (system unavailable or timed out).
        • S - Card type not supported. The card type for this transaction is not supported by AVS. AVS can verify addresses for Visa cards, MasterCard, proprietary cards, and private label transactions.
        • U - Address information unavailable.
        • G - Address information unavailable, International - Visa only, The address information was not available at the VIC or issuer's center.
        • W - Nine-digit ZIP match, address does not. The nine-digit Postal ZIP code matches that stored at the VIC or card issuer's centre. However, the first five numerical characters contained in the address do not match.
        • X - Exact match (nine digit ZIP and address). Both the nine-digit Postal ZIP code as well as the first five numerical characters contained in the address match.
        • Y - Address and five-digit ZIP match. Both the five-digit Postal ZIP code as well as the first five numerical characters contained in the address match.
        • Z - Five-digit ZIP matches, address does not. The five-digit Postal ZIP code matches that stored at the VIC or card issuer's centre.

        NOTE: Transactions can still be authorized if the AVS responses are no match or failure. AVS responses are for merchant information only, and usually do not influence the overall Authorization result. This can vary based on the Issuing Bank.

        Values are A, E, N, R, S, U, G, W, X, Y, or Z.

      • cvvResult string

        The CVV verification result. Typically returned on Card Not Present transactions.

        • M - CVV Match
        • N - CVV No Match
        • P - Not Processed
        • S - CVV should be on the card but the merchant indicates it is not.
        • U - User is unregistered

        NOTE: Transactions can still be authorized if the CVV responses are no match or failure. CVV responses are for merchant information only, and usually do not influence the overall Authorization result. This can vary based on the Issuing Bank.

        Values are M, N, P, S, or U.

      • accountType string

        The account type of the card (e.g. Credit or Debit)

      • hostResponseText string

        A meaningful text explaining the response code from the host.

      • receipt object

        The receipt associated with this transaction. Returned for Card Present transactions.

        Hide receipt attribute Show receipt attribute object
        • lines array[string]

          The receipt lines.

    • receipt object

      The receipt for the refund transaction, if available. If the original transaction was a Card Present transaction, the receipt will be included. For Card Not Present transactions, the receipt will be empty.

      Hide receipt attribute Show receipt attribute object
      • lines array[string]

        The receipt lines.
  • 400 application/json

    Request Error

    Hide response attributes Show response attributes object
    • code number

      Numeric error code. These are grouped into ranges for easier identification and troubleshooting.

      • 1000 - AuthenticationGenericError
      • 2000 - RequestValidationGenericError
      • 3000 - UnknownServerGenericError
      • 9000 - UnhandledGenericError

      Values are 1000, 2000, 3000, or 9000.

    • status string

      Execution status of the request sent to the payment gateway.

      • Completed - The request completed successfully.
      • Rejected - The request was rejected by the payment gateway. No action or side effects occurred. The transaction can safely be retried.
      • Interrupted - The request was interrupted, and the final status is unknown. Possible side effects may have occurred (e.g., a Sale (Token) that returns Interrupted might still charge the customer, even if an error is returned). Additional checks are required before retrying the transaction.
      • Unknown

      Values are Completed, Rejected, Interrupted, or Unknown.

    • message string

      Developer-facing error message.

    • traceId string

      Unique trace identifier for tracking and debugging this request.

    • timestamp string(date-time)

      The timestamp when the error occurred (UTC).

    • errorDetails array[object]

      Represents a validation error that occurred during the request.

      Hide errorDetails attributes Show errorDetails attributes object
      • code number

        Error code

      • field string

        The field with the error

      • message string

        Error message

      • details string

        Additional details about the error
  • 401 application/json

    Unauthorized response due to an invalid or missing API key.

    Hide response attributes Show response attributes object
    • code number

      Numeric error code. These are grouped into ranges for easier identification and troubleshooting.

      • 1000 - AuthenticationGenericError
      • 2000 - RequestValidationGenericError
      • 3000 - UnknownServerGenericError
      • 9000 - UnhandledGenericError

      Values are 1000, 2000, 3000, or 9000.

    • status string

      Execution status of the request sent to the payment gateway.

      • Completed - The request completed successfully.
      • Rejected - The request was rejected by the payment gateway. No action or side effects occurred. The transaction can safely be retried.
      • Interrupted - The request was interrupted, and the final status is unknown. Possible side effects may have occurred (e.g., a Sale (Token) that returns Interrupted might still charge the customer, even if an error is returned). Additional checks are required before retrying the transaction.
      • Unknown

      Values are Completed, Rejected, Interrupted, or Unknown.

    • message string

      Developer-facing error message.

    • traceId string

      Unique trace identifier for tracking and debugging this request.

    • timestamp string(date-time)

      The timestamp when the error occurred (UTC).

    • errorDetails array[object]

      Represents a validation error that occurred during the request.

      Hide errorDetails attributes Show errorDetails attributes object
      • code number

        Error code

      • field string

        The field with the error

      • message string

        Error message

      • details string

        Additional details about the error
POST /transactions/refund 
curl \
 --request POST 'https://api.omni.integratedcommerce.io/v1/transactions/refund' \
 --header "x-api-key: $API_KEY" \
 --header "Content-Type: application/json" \
 --data '{"amount":1000,"orderNumber":"order_number_1234","referenceId":"ref_refund_12345","invoiceNumber":"inv_1234567890123456789012354678901","originalTransactionId":"trx_01J2F0EKHC7HY2R93C8ENBD1FG"}'
Request examples 
{
  "amount": 1000,
  "orderNumber": "order_number_1234",
  "referenceId": "ref_refund_12345",
  "invoiceNumber": "inv_1234567890123456789012354678901",
  "originalTransactionId": "trx_01J2F0EKHC7HY2R93C8ENBD1FG"
}
{
  "amount": 1000,
  "orderNumber": "order_number_1234",
  "referenceId": "ref_refund_12345",
  "invoiceNumber": "inv_1234567890123456789012354678901",
  "originalReferenceId": "ref_s192i49i"
}
Response examples (200)
A successful response for a refund transaction. 
{
  "id": "trx_01J2F0ZJ2JW5B63CJFPXRGAB1S",
  "type": "Refund",
  "status": "Completed",
  "receipt": {
    "lines": [
      "     Test Merchant      ",
      "      300 S Wacker      ",
      "         Loop,          ",
      "                        ",
      "                        ",
      "TERM #          11000367",
      "RECORD #         0656191",
      "HOST INVOICE #    000038",
      "HOST SEQ #    1720656191",
      "MERCH                   ",
      "INVOICE inv_123456789012",
      "        3456789012354678",
      "        901             ",
      "------------------------",
      "CARD    ************0011",
      "VISA             Contact",
      "07/10/2024      20:03:05",
      "------------------------",
      "       VOID SALE        ",
      "                        ",
      "TOTAL         USD $10.00",
      "------------------------",
      "AUTH#:000AAA       B:171",
      "                        ",
      "      APPROVED 00       ",
      "       THANK YOU        ",
      "                        ",
      "      Visa Credit       ",
      "                        ",
      "                        ",
      "                        ",
      "                        ",
      "                        ",
      "                        ",
      "                        ",
      "     MERCHANT COPY      ",
      "     Test Merchant      ",
      "      300 S Wacker      ",
      "         Loop,          ",
      "                        ",
      "                        ",
      "TERM #          11000367",
      "RECORD #         0656191",
      "HOST INVOICE #    000038",
      "HOST SEQ #    1720656191",
      "MERCH                   ",
      "INVOICE inv_123456789012",
      "        3456789012354678",
      "        901             ",
      "------------------------",
      "CARD    ************0011",
      "VISA             Contact",
      "07/10/2024      20:03:05",
      "------------------------",
      "       VOID SALE        ",
      "                        ",
      "TOTAL         USD $10.00",
      "------------------------",
      "AUTH#:000AAA       B:171",
      "                        ",
      "      APPROVED 00       ",
      "       THANK YOU        ",
      "                        ",
      "      Visa Credit       ",
      "                        ",
      "                        ",
      "                        ",
      "                        ",
      "                        ",
      "                        ",
      "                        ",
      "     CUSTOMER COPY      "
    ]
  },
  "timestamp": "2025-05-27T18:49:31Z",
  "resultCode": 0,
  "resultText": "APPROVED",
  "orderNumber": "order_number_1234",
  "referenceId": "ref_s192i49i",
  "invoiceNumber": "inv_1234567890123456789012354678901",
  "paymentMethod": {
    "id": "pmt_tkn_01JRZPRGFF4J2SZC3HMDBYEN2J",
    "type": "Token",
    "cardType": "VISA",
    "currency": "USD",
    "cardExpDate": "1225",
    "description": "Token for John Doe's Visa",
    "maskedCardNumber": "************0011"
  },
  "approvedAmount": 1000,
  "requestedAmount": 1000,
  "transactionResponses": [
    {
      "authCode": "000AAA",
      "cardType": "VISA",
      "accountType": "Credit",
      "responseCode": 1,
      "paymentMethod": {
        "id": "pmt_tkn_01JRZPRGFF4J2SZC3HMDBYEN2J",
        "type": "Token",
        "cardType": "VISA",
        "currency": "USD",
        "cardExpDate": "1225",
        "description": "Token for John Doe's Visa",
        "maskedCardNumber": "************0011"
      },
      "amountApproved": 1000,
      "hostResponseText": "APPROVED 00"
    }
  ]
}
Response examples (400) 
{
  "code": 2000,
  "status": "Rejected",
  "message": "Refund request is invalid",
  "traceId": "1-687e7080-78cb54a51c8121ee32df9e35",
  "timestamp": "2025-06-21T16:53:20.9949208Z",
  "errorDetails": [
    {
      "code": 2000,
      "message": "Refund amount of 1000 exceeds the available balance of 0 for transaction ID trx_01J2F0EKHC7HY2R93C8ENBD1FG"
    }
  ]
}
Response examples (401) 
{
  "code": 1000,
  "status": "Rejected",
  "message": "API key cannot be empty",
  "traceId": "1-6838be96-74c62f8e2804352739e63476",
  "timestamp": "2025-05-29T20:07:50.4723483Z",
  "errorDetails": []
}