# 3. Refund

**Batch:** You can submit a transaction initiated via a batch payment order, along with its MerchantUniqueCode, to the Paywall APIs to process refunds for all transactions under that batch payment.

**List:** You can send payments identified by your MerchantUniqueCode values (which may be from batch or single transactions) as a single list to Paywall’s batch refund service. This allows you to complete refunds for all transactions with a single API call and receive a single callback notification from Paywall in response.


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