Booking flow for Source PSPs

Nexus does not prescribe the internal booking flow for PSPs (ie how and when they should debit the Sender/Debtor Account). However, payments submitted to Nexus cannot be stopped or recalled, meaning that payments in error can only be recovered by manual communication between the Source PSP and Destination PSP. Therefore the Source PSP should always ensure the payment can be processed on the account before sending the transaction.

This results in the following options for the Source PSP:

Option 1: Reservation followed by Booking

• The Source PSP validates the payment and make a funds reservation on the Sender’s account.

• The funds reservation must be upheld until the final response is received from the Source IPS.

• When the response indicates successful processing of the payment (either an ACCC or an ACWP response), the funds reservation results in a debit booking on the Sender’s account.

Option 2: Booking with optional reversal

• The Source PSP can also opt for the option of debiting the Sender’s account before sending the instruction to the Source IPS for further processing.

  • If the response is received with an ACCC or ACWP code, no further action is required.

  • In case the response indicates a RJCT code, the original debit on the Senders account must be reversed, resulting in a debit and credit booking.