A deposit ledger is the detailed record a bank, credit union or other account provider keeps for its customers' deposit accounts. For each account it lists every credit and debit, such as salary payments, card purchases, transfers, interest and fees, with dates and a running balance. It is a subsidiary ledger: the totals of all customer deposit accounts are summarised in the institution's general ledger, where they appear as liabilities.
The deposit ledger usually sits within the core banking system and is the source of balances shown in apps and statements. It distinguishes the ledger balance from the available balance, which also reflects pending items and holds. Regular ledger reconciliation checks that the deposit ledger agrees with the general ledger and with settlement accounts. Fintechs that hold customer funds at a partner bank often run their own ledger as well, which must match the bank's records.