A chart of accounts is the organized list of every category a company uses to classify its financial transactions, the categories that every expense, revenue line, asset, and liability actually get recorded under.
It's the backbone every other financial report is built from: an income statement, a balance sheet, and any category breakdown a founder cares about (marketing spend, payroll, software costs) all pull from how transactions were categorized in the chart of accounts in the first place.
A chart of accounts that's too generic, one giant "other expenses" bucket, makes the financials useless for understanding the business, while one that's too granular makes bookkeeping slow and inconsistent. Getting the structure right early, rather than recategorizing years of transactions later, is worth the setup time.
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