A ledger is a book or digital record containing all financial transactions of a business, organized by account. The general ledger is the master record from which financial statements are prepared.

Each transaction is recorded in the ledger using double-entry bookkeeping, with debits and credits. Modern accounting software maintains digital ledgers automatically. The ledger provides the foundation for financial reporting and analysis. Transactions are posted as journal entries that roll up into a trial balance, often in a core banking system.