Booking entries per message: pacs.008, pacs.004 and camt.056, with the debit and credit entry at each step

This lesson is the distinctive depth that separates a payments professional from a message reader: the exact debit and credit entry at each step, for a pacs.008, a pacs.004 return and a camt.056 recall. A message is an instruction, and a booking entry is the accounting, and the two must be linked by the message identifier, so that any message can be traced to its postings and any posting can be traced to its message. The examples below use real numbers and name the account, the direction and the bank at each step, and they are the pattern that a business analyst must be able to reproduce for any payment. Source: ISO 20022, pacs.008, pacs.004 and camt.056 message definitions; Bank for International Settlements, Committee on Payments and Market Infrastructures. Start with a pacs.008 customer credit transfer of EUR 50,000 from a customer of Bank A in Paris to a supplier at Bank B in Berlin, settled through T2. At Bank A the posting is debit customer deposit account EUR 50,000 and credit T2 settlement account EUR 50,000, on the value date, with the pacs.008. At the central bank the posting is debit Bank A reserve account EUR 50,000 and credit Bank B reserve account EUR 50,000. Three banks, six postings, and every debit has a matching credit, so the payment is fully accounted for, and the camt.053 statement for each account will show the entry with the message identifier as the reference. Now the pacs.008 reaches Bank B. Bank B cannot credit the supplier, so it returns the payment with a pacs.004, reason code AC04 for a closed account, for the full EUR 50,000. At the central bank the posting is debit Bank B reserve EUR 50,000 and credit Bank A reserve EUR 50,000. At Bank A the return posts as debit T2 settlement account EUR 50,000 and credit customer deposit account EUR 50,000, so the customer is refunded in full. The original pacs.008 and the pacs.004 are linked by the original message identifier, which the pacs.004 carries as the return reference, and the reconciliation must prove that the payment and the return net to zero across both banks, with the customer balance restored. Next the camt.056 recall, because the customer of Bank A sent the EUR 50,000 to the wrong supplier and asks Bank A to recall it. Bank A sends a camt.056 FI to FI payment cancellation request to Bank B, citing the original pacs.008 message identifier, the amount EUR 50,000 and the reason DUPL for a duplicate payment. No posting is made on receipt of the camt.056. Bank B then sends a pacs.004 return for EUR 50,000, and the postings follow the return pattern above: Bank B debits the beneficiary account and credits the settlement account, and Bank A debits the settlement account and credits the customer. Bank B also sends a camt.029 resolution of investigation, confirming the recall was accepted, and the case is closed. The camt.056 is the recall request. The first option is a pacs.004 return. The second option is a camt.029 resolution of investigation with a positive outcome, followed by a separate return instruction, or, in some schemes, a pacs.008 in the opposite direction, where the beneficiary instructs a new credit transfer back to the original debtor. The postings for the second option are a new payment, not a return, so the beneficiary bank debits the beneficiary account and credits the settlement account as a new pacs.008, and the original debtor bank credits the customer as a new receipt. The business analyst must state which option the scheme uses, because the message, the reason code and the reconciliation are different. The nostro and vostro mirror treatment is the cross-border version of the same pattern, and it must be stated explicitly. When Bank A in London pays USD 100,000 to Bank B in New York through a nostro account, Bank A posts debit customer deposit USD 100,000 and credit nostro account at Bank B USD 100,000. Bank B, which holds the account as a vostro account, posts debit vostro account USD 100,000 and credit beneficiary deposit USD 100,000. If Bank B also holds a mirror account, which is a shadow copy of the nostro used for reconciliation, the mirror must agree with both, and any difference is a break that must be investigated as a nostro break, not as a customer break. Failure in the booking entries is a posting failure, and the recovery is a correcting entry. If the pacs.008 is sent but the customer debit is not posted, the bank has sent money it has not debited, and the trial balance will fail by EUR 50,000, so the missing debit must be posted with the original value date, not the discovery date, and the interest must be adjusted. If the pacs.004 return is posted twice, the customer is credited twice, and the duplicate credit must be reversed with a correcting debit, with the original credit left visible in the audit trail. If the camt.056 recall is rejected, the original payment stands, and the customer must be told. Each failure is found by reconciliation, and each correction is a new posting, never an edit or a deletion. For a business analyst, product owner or subject matter expert, this lesson is the test of whether a requirement is complete. For every message in the product, write the posting table: message, bank, debit account, credit account, amount, currency, value date and reference. Ask what happens when one leg posts and the other fails, how the system recovers, and how the reconciliation proves the recovery. The ISO 20022 messages carry the instruction and the reference, the ledger carries the money, and the posting table is the link between them, and a functional specification without it is incomplete, however detailed its message mapping is. The accounting also decides the customer communication. When a customer asks why a return took two days, the answer is in the value dates of the return postings. When a customer asks why a recall failed, the answer is in the camt.029, which states whether the beneficiary agreed. A business analyst who can read the postings can answer the customer, the operations team and the auditor from the same source, and that is the skill this lesson teaches. The sources for the message definitions are the ISO 20022 message definitions on iso20022. org, and for the settlement rules, the EPC SEPA Credit Transfer Rulebook 2025, version 1. 1, effective 5 October 2025. Takeaway: a pacs.008 posts a debit to the debtor and a credit to the settlement account at the debtor bank, and the mirror at the creditor bank, with the central bank moving reserves between them. A pacs.004 reverses the entries, with reason code AC04 for a closed account. A camt.056 posts nothing until the beneficiary bank agrees, and the positive response is either a pacs.004 return or a new payment, with different postings. Nostro and vostro are mirror postings of the same account. Further reading: ISO 20022, pacs.008, pacs.004 and camt.056 message definitions; European Payments Council, SEPA Credit Transfer Rulebook 2025, version 1.1, effective 5 October 2025. Last reviewed 7 November 2026.