Plain definition
A three-statement model links the income statement, balance sheet, and cash flow statement. Revenue and costs affect profit; profit, investment, borrowing, and working capital change assets, liabilities, and equity; those movements explain the change in cash. The links force the forecast to tell one consistent story.
It is especially useful for growth plans because growth can raise reported profit while consuming cash. Extra sales may create receivables and inventory before customers pay. A model that forecasts the income statement alone can miss the funding requirement created by that timing.
Illustrative example
Monetary examples use Saudi riyals (SAR). The same principles apply in other currencies.
Suppose a company forecasts of additional annual sales. It expects a 30% gross margin, but customers pay after 60 days and inventory must be bought before delivery. The model records profit from the sales, the increase in receivables and inventory, the related payables, and the resulting cash need.
If ending cash becomes negative while profit is positive, the forecast has exposed a financing decision rather than an accounting error. Management can alter payment terms, slow growth, use supplier credit, or obtain funding. Each choice should flow through all three statements.
The statements need not be perfect forecasts. They must be internally consistent and explicit about the assumptions that connect them.
Why it matters
Founders can mistake a growing profit line for a funded plan. The three-statement link reveals whether the same growth requires cash the company does not have, or creates debt and covenant pressure that the income statement does not show.
Practical consequence
Build the income statement first from operational drivers, then model working-capital, capital-spending, debt, and equity movements on the balance sheet. Derive the cash movement from those changes and check every period: assets equal liabilities plus equity, retained earnings tie to profit and distributions, debt rolls forward, and ending cash agrees across the model.