The Three-Statement Model: The Foundation of Everything in Finance

Every DCF, LBO, and M&A model starts with the same thing: a three-statement model. It's the foundation. If you can't link an income statement, balance sheet, and cash flow statement together, nothing else works.

The good news is that once you understand how the three statements connect, every other model is just a variation on the same theme.

What is a Three-Statement Model?

A three-statement model projects a company's Income Statement, Balance Sheet, and Cash Flow Statement into the future — typically 3-5 years — with all three statements dynamically linked.

"Dynamically linked" is the key phrase. Change revenue growth and it flows through to EBITDA, affects tax, changes net income, which hits retained earnings on the balance sheet, which changes the cash flow statement, which changes the cash balance, which changes the interest income, which changes net income... and around we go.

That circular reference between interest expense and net income is why three-statement models are considered the first real test of a financial modeler. You need a circularity solver or iterative calculation to make it work.

Why It Matters

You can't value a company without projecting its financials. And you can't project financials without understanding how the three statements interact.

DCF models need projected free cash flows — which come from the three-statement model

LBO models need operating cash flow to determine how fast debt gets paid down

M&A models need pro forma financials for the combined entity

Credit analysis needs projected leverage and coverage ratios

In interviews, if someone asks you to build a DCF from scratch, they expect you to start with a three-statement model. Skipping straight to "take FCF and discount it" shows you don't understand where the numbers come from.

How the Three Statements Link

Income Statement to Balance Sheet

Net income flows to retained earnings. That's the primary link. But there are others:

Depreciation expense on the IS reduces PP&E on the BS

Interest expense depends on the debt balance

Tax expense creates deferred tax assets/liabilities

Balance Sheet to Cash Flow Statement

The cash flow statement explains the change in cash on the balance sheet. It starts with net income and adjusts for:

Non-cash charges (depreciation, amortization) — add back

Working capital changes — increases in AR and inventory use cash, increases in AP provide cash

Capex — reduces cash, increases PP&E

Debt issuance/repayment — affects both the BS debt balance and CFS financing section

Dividends — reduce cash and retained earnings

The Circularity

Here's where it gets interesting. Interest expense depends on the debt balance. But the debt balance depends on cash flow. And cash flow depends on interest expense.

You can't solve this with a single pass. You need either:

Iterative calculation — run the model multiple times until it converges

A circularity solver — programmatically iterate until the difference between passes is negligible

Most Excel models use iterative calculations (the circular reference toggle in settings). Prova's three-statement model has a built-in circularity solver that converges in about 10 iterations.

Key Drivers to Understand

When building a three-statement model, these are the assumptions that matter most:

Revenue growth — everything flows from revenue. Get this wrong and everything downstream is wrong too.

Cost structure — COGS as a % of revenue, SG&A as a % of revenue, R&D spend. Are margins expanding or contracting?

Working capital days — DSO (days sales outstanding), DIO (days inventory outstanding), DPO (days payable outstanding). These determine how much cash is trapped in operations vs. available for other uses.

Capital expenditure — how much does the company need to invest in PP&E to sustain and grow the business?

Debt terms — interest rate, mandatory repayment schedule, revolving credit facility.

The Balance Sheet Check

A properly built three-statement model must balance: Assets = Liabilities + Equity, every year. If it doesn't balance, something is wrong with your links.

Common mistakes that break the balance:

Forgetting to flow net income to retained earnings

Not adjusting PP&E for both capex and depreciation

Missing the cash flow impact of working capital changes

Incorrect debt schedule (payments not reducing the balance)

Try It Yourself

Prova's three-statement model auto-fills from live ticker data — revenue, cost structure, working capital days, PP&E, debt, everything. Type any ticker and get a fully linked IS/BS/CF with circularity solver, vintage depreciation tracking, and NOL carryforward.

Build a Three-Statement Model Free