Three-Statement Model: A Founder's Practical Guide

Most founders have looked at a profit and loss statement. Fewer have looked at a balance sheet with any confidence. Almost none have sat down and connected all three core financial statements into a single, living model, which is exactly why so many growing companies get surprised by a cash crunch even in a "good" month.

A three-statement model ties your income statement (P&L), balance sheet, and cash flow statement together so that a change in one flows through the others automatically. It is the foundation of any serious financial forecast. Here is how to build a simple version that actually works.

Why three statements, not just a P&L

The P&L answers one question: are you profitable? It is useful, but it is not the whole picture. Profit and cash are not the same thing. You can be profitable on paper while running out of money in your bank account, because the P&L ignores timing: when customers actually pay, when you pay suppliers, when VAT hits your account, how debt repayments move.

The balance sheet captures what the company owns and owes at a point in time. Assets, liabilities, equity. It is a snapshot.

The cash flow statement bridges the two: it starts with net profit and walks through every reason cash actually moved differently from what the P&L showed.

When you connect all three, you get a model that tells you not just whether the business is profitable, but whether it is solvent, and what happens to both if you change one assumption.

The structure: what goes where

Start with these three sheets in your spreadsheet. Keep them separate but linked.

The income statement contains:

• Revenue (by product, service line, or customer segment, whatever is most useful)
• Cost of goods sold or direct costs
• Gross profit
• Operating expenses (salaries, rent, subscriptions, marketing, and so on)
• EBITDA
• Depreciation and amortisation
• EBIT (operating profit)
• Interest income and expense
• Tax
• Net profit

The balance sheet contains:

• Assets: cash, accounts receivable, inventory, fixed assets, prepaid costs
• Liabilities: accounts payable, short-term debt, VAT payable, accrued costs, long-term debt
• Equity: share capital, retained earnings (which ties to cumulative net profit from the P&L)

The cash flow statement contains:

• Cash from operations (net profit adjusted for non-cash items and working capital changes)
• Cash from investing (asset purchases, disposals)
• Cash from financing (loans taken, repaid, equity injections, dividends)
• Net change in cash (which ties directly to the cash line on the balance sheet)

The three links that make the model work

The magic of a three-statement model is three specific connections. Get these right and the model is coherent. Get them wrong and you are just maintaining three separate, inconsistent spreadsheets.

Link 1: Net profit feeds retained earnings. The bottom line of your P&L rolls into the equity section of the balance sheet. Each period, retained earnings increase or decrease by net profit or net loss for that period. This is how the balance sheet stays balanced as the business operates.

Link 2: The cash flow statement starts with net profit. Your operating cash flow section begins with net profit from the P&L, then adjusts for non-cash items (depreciation is the most common) and changes in working capital (if receivables increase, cash is lower than profit suggests; if payables increase, cash is higher).

Link 3: Ending cash on the cash flow statement equals cash on the balance sheet. The net change in cash from the cash flow statement, added to opening cash, gives you your closing cash balance. That number must match the cash line on the balance sheet for the same period. If it does not, something is wrong.

Building the forecast: a step-by-step approach

Once the structure is in place, you populate it forward in time.

Step 1: Forecast revenue. Start with what you know: signed contracts, recurring revenue, historical run rate. Add a realistic view of new business. Break it down by month.

Step 2: Forecast direct costs. These typically move with revenue. If your gross margin is fairly stable, you can model direct costs as a percentage of revenue.

Step 3: Forecast operating expenses. Most of these are relatively fixed: salaries, rent, known subscriptions. Model them line by line based on what you have committed to and what you plan to hire.

Step 4: Let the P&L calculate net profit automatically for each period.

Step 5: Model working capital assumptions. How many days does it typically take customers to pay you? How many days do you take to pay suppliers? These assumptions drive accounts receivable and accounts payable on the balance sheet, which in turn affect operating cash flow.

Step 6: Add any planned investments or financing. A planned equipment purchase hits investing cash flow and increases fixed assets. A new loan hits financing cash flow and increases both cash and debt.

Step 7: Check the three links. Net profit into retained earnings. Cash flow statement starting from net profit. Ending cash matching the balance sheet. If the balance sheet does not balance (assets not equal to liabilities plus equity), trace it back to a broken link.

Common mistakes that break the model

Mixing cash and accrual accounting in the same statement. Pick one basis and be consistent. For a forecast, accrual is almost always more useful because it shows economic activity when it happens, not just when cash moves.

Forgetting VAT. VAT collected from customers sits as a liability on the balance sheet until you pay the Swedish Tax Agency. If you model revenue including VAT, your accounts receivable and cash will both be overstated unless you account for the VAT payable. The simplest approach is to model revenue net of VAT throughout.

Ignoring payroll taxes and employer contributions. Salary cost in the P&L should include the full employer cost (lönekostnader plus social avgifter), not just the gross salary the employee sees. Otherwise your margin looks better than it is.

Not updating the model. A forecast that is three months stale is not a forecast, it is a historical document. The model earns its value when you update actuals each month, compare to the forecast, understand the variances, and revise the outlook forward.

What a working model actually tells you

Once the three statements move together, a few questions become trivially easy to answer:

• If we hire two people in Q3, when do we feel it in cash?
• If our largest customer delays payment by 30 days, do we still meet payroll?
• At current burn, how many months of runway do we have?
• If revenue comes in 15% below plan, what do we need to cut to stay cash-positive?

These are the questions that matter when you are running a company. A single P&L cannot answer them. A connected three-statement model can.

When to hand this off

Building the first version of this model yourself is worth doing once, because it forces you to understand how your business's numbers connect. But maintaining it every month, keeping it accurate, stress-testing scenarios, and turning it into the board-ready analysis your investors or leadership team actually need, that is where the time cost stops making sense for a founder or CEO.

If you want a model that stays current without finance sitting on your plate, book a 30-minute demo with Victor Pernvik. We build and maintain this kind of forecasting infrastructure as part of the full finance function we run for 60+ Swedish growth companies.