Both the Payer and Requester of Batch Payments get notified if a payment is Failed/Cancelled/Rejected, or was processed successfully (fully or partially).
The Payer also gets notified when a Batch Payment is fully Approved and is Awaiting Payment.
Please note: Very rarely, payments are made but some time later the Failed status is returned; for example, if there's a typo in the beneficiary's account number.
In this case, both the Payer and Requester will first be notified about the successful payment and later receive a notification that this particular payment has failed. After 3 days, Failed payments are Cancelled and a notification is sent to the Requester and Payer.