# Partially refund a balance

## Object

Name Description
MerchantPos  POS object representing the cash register application.

## Method

Name

Description

RefundAtPspRequest

Call used to initiate a par tial refund where the PSP reference is unknown.

This can happen when the original sale transaction was performed offline, in which case there will be no PSPReference, since this is generated only in an online situation.

## Parameters

There are two ways to perform a partial refund:

1. the pspReference is known: In this case, only the pspReference needs to be provided, the properties TerminalId and TenderReference are not required.

2. the pspReference is NOT known: This can happen when the original Sale transaction was performed offline, in which case there will be no pspReference, since this is generated only in an online situation.

In this case, the properties TerminalId and TenderReference need to be provided, the property PspReference is not required.

Name Type Required Description
merchantAccount String The merchantAccount account to receive the money
modificationCurrency String The currency of the refunded amount
modificationAmount long The refunded amount. Can be smaller than the initial amount, or in the limit defined per merchant
merchantReference String The unique merchant reference
pspReference String The unique PSP reference.
tenderReference String The unique tender reference. In offline situation, the cash register may not have the PSP reference. The tenderReference in combination with terminalId need to be send in the request.
terminalId String The unique ID of the terminal on which the original transaction is performed.

## Callback

NameDescription

refundAtPspCallback

Refund Callback returns the result of a partial refund, as well as any errors. Returns an adyenResult RefundAtPspResult with the transaction result details