Money on a bank balance sheet

A bank balance sheet shows money from two sides at once, and reading it correctly is a core skill for a payments professional. On the asset side sit the claims the bank holds on others: cash, reserves at the central bank, loans, securities and nostro balances at other banks. A customer deposit of EUR 100,000 is an asset for the customer and a liability for the bank, and the same EUR 100,000 is an asset for the bank only when it is held as cash or reserves or lent onward. The balance sheet always balances, because every liability is matched by an asset, and a payment moves entries on both sides at once. Source: Bank for International Settlements, Committee on Payments and Market Infrastructures; Bank of England, How is money created. The mechanism is double-entry bookkeeping, and a payment is a set of postings, not a physical movement. When a customer deposits EUR 10,000 in cash, the bank debits cash, an asset, and credits the customer deposit account, a liability. When the customer then pays EUR 10,000 to a customer of another bank, the bank debits the customer deposit account and credits its reserve account at the central bank, or credits its nostro account, depending on the settlement route. When the receiving bank credits its customer, it debits its reserve account and credits the customer deposit. At each step the debits equal the credits, and the balance sheet of each bank still balances. A payment that posts only one side is not a payment, it is a break, and reconciliation exists to find it. A worked example with real numbers shows the whole picture. A customer of Bank A pays EUR 2 million to a customer of Bank B through T2. Bank A debits the customer deposit, so deposits fall to EUR 498 million, and credits its reserve account down, so reserves fall to EUR 48 million, and assets fall to EUR 498 million, so the sheet still balances. Bank B does the mirror: reserves rise to EUR 52 million, deposits rise to EUR 502 million, and its sheet balances. No money was created or destroyed, it moved from one bank balance sheet to another through the central bank, and the customer balances are the record of who owns the claim at each step. Why this matters for payments is that lending creates commercial bank money, and repayment destroys it. When Bank A lends EUR 1 million to a business, it credits the business deposit account, a liability, and debits loans, an asset, and the money supply has grown by EUR 1 million, because a new deposit exists. When the business repays the loan, the deposit is debited and the loan is reduced, and the money supply shrinks. A payment hub that authorises a payment without checking the reserve position or the intraday liquidity is authorising a posting the bank cannot settle, and the payment will fail at the settlement step. Failure on the balance sheet appears as a mismatch, and the mismatch has a name in operations: a break. If a nostro statement shows a credit that the bank ledger does not, the difference sits in a suspense account until it is matched or investigated. If a bank lends too much against too little capital, the regulator intervenes, because the balance sheet no longer protects depositors. The 2008 financial crisis and the 2023 bank failures both turned on balance sheet questions, and the payment system was the channel through which the stress spread, because payments are the daily test of whether a bank can meet its liabilities. The effect on the bank, the customer and operations is that every payment is a balance sheet event. For the customer, a deposit is a claim on the bank, and the customer bears the bank credit risk above the deposit guarantee limit. For the bank, a payment changes its liquidity, its reserve position and its capital ratios, and treasury must fund the reserve outflow before the payment is released. For operations, the ledger must post both sides of every payment, the sub-ledger must agree with the general ledger, and the nostro and central bank statements must agree with the ledger at the end of the day. A product that promises instant credit to a customer before the bank has the reserves to settle is promising a balance sheet event the bank has not funded. For a business analyst, product owner or subject matter expert, the balance sheet is the test of whether a requirement is complete. Ask which balance sheet lines move, in which direction, and by how much, for every payment, return, recall and fee. Ask what happens to capital and liquidity when the payment is large, and who approves the funding. The ISO 20022 messages carry the instruction, but the ledger carries the money, and a requirement that describes only the message and not the posting is half a requirement. The payment engine, the ledger and the reconciliation engine must be specified together, or the product will pass its message tests and fail its accounting tests. Money on a balance sheet also explains the difference between a payment and a loan, and between a payment and a transfer of an asset. A payment moves a claim from one holder to another, and the total claims in the system stay the same. A loan creates a new claim and a new deposit, and the total grows. A securities settlement moves an asset and a payment together, and the two legs must settle together or not at all, which is why delivery versus payment exists. A business analyst who confuses these three will write the wrong posting rules, the wrong reconciliation and the wrong failure handling, and the error will surface at the first end of day close, when the books do not balance. Takeaway: every payment is a balance sheet event, with a debit and a credit that must be equal, and a customer deposit is a liability of the bank while reserves at the central bank are an asset. Lending creates commercial bank money, repayment destroys it, and settlement moves reserves between banks. Name the balance sheet lines, the direction and the amount for every payment, return and fee. Further reading: Bank of England, Money creation in the modern economy; Bank for International Settlements, Committee on Payments and Market Infrastructures, A glossary of terms used in payments and settlement systems. Last reviewed 7 November 2026.