running balance
A running balance is an account's balance recalculated and shown after every single transaction, rather than only at the end. It is exactly like the 'balance' column in a personal checkbook or a banking app: each time money moves, a new up-to-date balance appears on that line, so you can see at any moment where the account stands without having to total everything from scratch.
This is the format of a three-column (or 'balance-column') ledger account: columns for debit, credit, and balance. After each posting, you adjust the previous balance — add if the new amount is on the account's normal side, subtract if it is on the opposite side — and write the result. If Cash starts at 9,800 (debit) and you post a 600 credit (cash paid out), the new running balance becomes 9,200 on the very next line. The final running balance equals the account balance you would get by netting all debits and credits at once.
Running balances are how almost all real and computerized ledgers display accounts today, because they answer 'how much now?' instantly and make it easy to spot the moment a balance went wrong or, for cash, the moment it would go negative. The trade-off is that every line depends on the line above it: one mis-posted amount throws off every running balance after it, so the convenience comes with a need for careful, in-order recording.
A Cash ledger with a balance column: start 10,000 (debit). Post a 600 credit → balance 9,400. Post an 800 debit → balance 10,200. Post a 400 credit → balance 9,800. Each line shows the up-to-the-second balance.
The balance column updates after every posting, so the current total is always visible.
Because each running balance builds on the one before it, a single error propagates downward. The figure is convenient but only as trustworthy as every posting above it.