The part most guides skip. The statements are plumbed into each other, so changing one number ripples through all three.
4 min readIntermediateUpdated July 2026
Key takeaways
Net income flows from the Income Statement into equity on the Balance Sheet.
Net income also starts the Cash Flow Statement, which ends in the change to the cash line.
This linkage is why analysts build a single "three-statement model".
The plumbing
Here’s where finance goes from three separate reports to one elegant machine: the statements are plumbed into each other. Specific numbers flow from one to the next, always in the same pattern:
Net income flows to the Balance Sheet. The profit at the bottom of the Income Statement gets added to retained earnings in equity. Profit literally becomes ownership value.
Net income also starts the Cash Flow Statement. Operating cash flow begins with profit, then adjusts for everything that affected profit without moving cash, and cash that moved without touching profit.
The net change in cash lands back on the Balance Sheet. The last line of the Cash Flow Statement is exactly the change in the cash line between one balance sheet and the next. The loop closes.
Why it’s called a three-statement model
Change one assumption, say revenue grows 20% instead of 10%, and the effect ripples through profit, into equity, and through cash, automatically and consistently. Three gauges wired to one engine.
This is what the builder does
In Koala’s builder the plumbing is pre-wired: edit any line and net income, retained earnings, and cash all update together, with the balance sheet kept in balance.
See it in a real model
The fastest way to make this stick is to build one and watch the numbers move.