How can I refund transactions on Merchant account?

You have to refund each transaction one by one.

You can do this from either your Revolut Business app (see below) or using the Merchant API using the Refund endpoint.

Go to 'Payments' menu
Open 'Requests' tab
Select the payment you want to refund (click 'See all' if you can't see older payments)
On the info panel, click 'Refund'
Fill in details and continue
Confirm to refund the payment

To partially refund a transaction, select an amount lower than the total value of the original payment.

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