A 3-statement financial model is the foundation of everything in investment banking. Whether you’re building a DCF, an LBO model, or a merger model, it all starts with a properly built 3-statement model. In this guide, we’ll walk through the entire process of building one from scratch, from setting up assumptions to linking the three financial statements and handling circularity.
If you need a refresher on how the income statement, balance sheet, and cash flow statement relate to each other, start with our guide on how the three financial statements link together. That conceptual foundation will make this guide much easier to follow.
What Is a 3-Statement Financial Model?
A 3-statement model is an integrated Excel model that projects a company’s income statement, balance sheet, and cash flow statement into the future. “Integrated” is the key word here: the three statements are dynamically linked so that a change in one statement automatically flows through to the others. This is what makes the model powerful and realistic.
In investment banking, 3-statement models are used for:
- Valuation: Projecting free cash flows for a DCF analysis
- Credit analysis: Assessing a company’s ability to service debt
- M&A analysis: Combining two companies’ financials in a merger model
- LBO modeling: Projecting cash flows to determine debt paydown and returns
- Scenario analysis: Testing how changes in assumptions affect financial outcomes
Step 1: Gather Historical Data and Set Up the Spreadsheet
Start by pulling 3-5 years of historical financial data from the company’s SEC filings (10-K and 10-Q reports). Organize your spreadsheet with historical years on the left and projection years on the right. Color-code your model: blue for inputs/assumptions, black for formulas, and green for links to other sheets. This is standard banking convention and makes your model auditable.
Key sections to set up:
- Assumptions page: Revenue growth, margin assumptions, working capital days, capex, D&A, tax rate, interest rate, etc.
- Income statement
- Balance sheet
- Cash flow statement
- Supporting schedules: Depreciation schedule, debt schedule, working capital schedule
Step 2: Build the Income Statement
The income statement is typically the first statement to project because many balance sheet and cash flow items are driven off of income statement line items.
Revenue
Revenue is the most important assumption in any model. There are several approaches:
- Top-down: Apply a growth rate to total revenue (e.g., 8% YoY growth)
- Bottom-up: Build revenue from individual drivers (units x price, subscribers x ARPU, same-store sales growth + new store openings)
- Segment-based: Project each business segment separately and sum them
The bottom-up approach is more defensible in interviews and on the job because it ties to real business drivers. Start with a top-down sanity check, then build the detail.
Cost of Goods Sold and Gross Profit
Project COGS as a percentage of revenue (gross margin assumption). Look at historical trends and management guidance. For most companies, gross margins are relatively stable unless there’s a clear reason for expansion or compression.
Operating Expenses
Project SG&A, R&D, and other operating expenses as a percentage of revenue or as fixed/variable components. Be thoughtful about operating leverage: as companies grow, certain fixed costs may decline as a percentage of revenue.
D&A, Interest Expense, and Taxes
These line items link to other schedules:
- D&A: Comes from the depreciation schedule (linked to PP&E and capex)
- Interest expense: Comes from the debt schedule (average debt balance x interest rate). This is where circularity arises (more on that later).
- Taxes: Apply the effective tax rate to pre-tax income. Note that you should use the effective (not statutory) rate unless you have a reason to adjust.
Step 3: Build the Balance Sheet
The balance sheet captures the company’s assets, liabilities, and equity at a specific point in time. Many balance sheet line items are driven by income statement metrics.
Working Capital
Working capital items are typically projected using “days” metrics:
- Accounts Receivable: Days Sales Outstanding (DSO) = AR / Revenue x 365
- Inventory: Days Inventory Outstanding (DIO) = Inventory / COGS x 365
- Accounts Payable: Days Payable Outstanding (DPO) = AP / COGS x 365
To project forward, assume stable days (or trending toward a target) and solve for the balance sheet amount. For example: Projected AR = DSO assumption x (Projected Revenue / 365).
PP&E and Capex
The PP&E schedule follows this logic:
Ending PP&E = Beginning PP&E + Capital Expenditures − Depreciation
Capex is often projected as a percentage of revenue. Depreciation is typically calculated as a percentage of beginning PP&E or the average useful life of the company’s assets.
Debt
The debt schedule tracks the beginning balance, any new borrowings, mandatory repayments (amortization), and optional repayments. This is a critical schedule for LBO models. Interest expense on the income statement is calculated from the debt balances here.
Shareholders’ Equity
The equity roll-forward is:
Ending Equity = Beginning Equity + Net Income − Dividends + Stock Issuance − Share Buybacks + Other Comprehensive Income
Retained earnings increases by net income and decreases by dividends. Share-based compensation is usually a separate line item.
Step 4: Build the Cash Flow Statement
The cash flow statement ties the income statement and balance sheet together. It explains why cash changed from one period to the next.
Cash Flow from Operations
Start with net income and make adjustments:
- Add back non-cash charges: Depreciation, amortization, stock-based compensation
- Adjust for working capital changes: Increases in current assets are cash outflows; increases in current liabilities are cash inflows
The working capital changes come from the balance sheet projections. For example, if AR increases from $100M to $120M, that’s a $20M use of cash (you earned the revenue but haven’t collected it yet).
Cash Flow from Investing
This section captures capital expenditures (from the PP&E schedule), acquisitions, asset sales, and changes in other long-term assets. In a basic model, capex is the primary investing activity.
Cash Flow from Financing
This includes debt issuance and repayment (from the debt schedule), dividend payments, share issuances, and share buybacks. The financing section is where you see the capital structure decisions flow through.
The Final Link
The sum of cash from operations, investing, and financing equals the net change in cash. Add this to beginning cash to get ending cash, which should match the cash balance on the balance sheet. If these don’t match, your model has an error. This is the most important check in any 3-statement model.
Step 5: Handle the Circularity
Here’s where things get tricky, and where interviewers love to test you. A 3-statement model has a natural circularity:
- Interest expense (on the income statement) depends on the debt balance (on the balance sheet)
- The debt balance depends on available cash flow (from the cash flow statement)
- Cash flow depends on net income (from the income statement), which includes interest expense
This creates a circular reference in Excel. There are two common approaches to handle it:
Option 1: Enable Iterative Calculations
In Excel, go to File > Options > Formulas and check “Enable iterative calculation.” Excel will run through the circular calculation multiple times until it converges on a stable answer. This is the most common approach in practice: most banks use iterative calculations.
Option 2: Use a Circularity Breaker
Create a toggle switch (a cell that’s either 1 or 0). When set to 1, the model calculates interest on the average debt balance. When set to 0, it calculates interest on the beginning debt balance (which breaks the circularity). If the model breaks, flip the switch to 0, let it recalculate, then flip back to 1. This is the safer approach and preferred by many modeling best-practice guides.
Step 6: Build Supporting Schedules
A robust 3-statement model includes several supporting schedules:
- Depreciation schedule: Tracks existing PP&E depreciation and depreciation on new capex additions by vintage year
- Debt schedule: Shows all debt tranches, beginning/ending balances, amortization, and interest expense calculations
- Working capital schedule: Details the days assumptions and resulting balance sheet and cash flow impact for each working capital item
- Tax schedule: Reconciles book vs. cash taxes, tracks deferred tax assets/liabilities and NOL carryforwards
- Share count schedule: Tracks basic shares, options, RSUs, and the diluted share count using the treasury stock method
Step 7: Error Checks and Sanity Tests
Before presenting your model, always run these checks:
- Balance sheet balances: Assets = Liabilities + Equity in every period. Create a check row that flags any imbalance.
- Cash flow reconciliation: Ending cash on the cash flow statement matches the balance sheet.
- Revenue growth sanity: Are the projected growth rates reasonable relative to the industry and management guidance?
- Margin trends: Are margins expanding/compressing in a way that makes sense?
- Debt covenants: Does the company maintain acceptable leverage and coverage ratios?
- Negative cash balance: If cash goes negative, the model is broken, and the company would need to raise capital or draw on a revolver.
Common Interview Questions About 3-Statement Models
- “Walk me through how the three financial statements are linked.”: Net income flows from the income statement to the top of the cash flow statement and into retained earnings on the balance sheet. Non-cash charges are added back on the CFS. Changes in working capital items on the balance sheet appear on the CFS. Capex on the CFS reduces PP&E on the balance sheet. Debt changes on the CFS match the balance sheet, and interest flows to the income statement. For a full walkthrough, see our guide on how the three financial statements link together.
- “What’s the circularity in a 3-statement model?”: Interest expense depends on debt, debt depends on cash flow, and cash flow depends on net income which includes interest. You resolve it with iterative calculations or a circularity breaker toggle.
- “If revenue increases by $100, walk me through the impact on all three statements.”: Income statement: revenue +$100, assuming 40% operating margin, operating income +$40, after 25% taxes, net income +$30. Cash flow statement: net income +$30, but working capital increases (e.g., AR +$15, inventory +$10), offset by AP +$5, net cash from operations roughly +$10. Balance sheet: cash increases by net change in cash, AR and inventory increase, AP increases, retained earnings +$30.
- “What are the most important assumptions in a 3-statement model?”: Revenue growth, operating margins, working capital efficiency, capex intensity, and the tax rate. A sensitivity analysis on these key drivers is essential.
Tips for Acing Modeling in Interviews
Many banks include a modeling test as part of the interview process. Here’s how to prepare:
- Practice building models from scratch. Download a 10-K and build a 3-statement model without a template. Do this at least 5-10 times with different companies.
- Know the formulas cold. You should be able to project every major line item without looking anything up. Our technical cheatsheet is a great study reference.
- Build for speed and accuracy. Modeling tests are timed. Use keyboard shortcuts, avoid the mouse, and build clean formulas that are easy to audit.
- Always check your work. A model that doesn’t balance is worse than an incomplete model. Build in error checks from the start.
- Understand the “so what.” After building the model, be prepared to discuss what the outputs tell you about the company’s financial health, valuation, and creditworthiness.
For more preparation resources, check out our free course and free resources page. And if you’re working on your application materials, don’t miss our investment banking resume guide and cover letter guide.
Want Personalized Interview Coaching?
Building a 3-statement model is one thing, and doing it under time pressure in an interview while explaining your thought process is another. At Wall Street Mastermind, our coaches run live modeling sessions with you and provide real-time feedback so you’re fully prepared for any modeling test. We’ve helped over 2,500 students break into top finance firms. Apply today to learn more about our program.
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