How do you turn financial statements into free cash flow?

A DCF eats free cash flow — the real, spendable cash a business produces after keeping itself running. Profit ("net income") isn't quite it, because profit includes non-cash items and ignores the cash tied up in growing. Let's build free cash flow from statements you already know how to read.

Cash, not profit

Start from the top of the income statement and walk down to cash:

• Revenue — the sales the business made.
• minus operating costs → operating profit (what the core business earns before financing and tax).
• The cash flow statement then adds back depreciation (a bookkeeping charge, not a cash payment) and adjusts for working capital (cash trapped in inventory and unpaid invoices, or freed up).
• The result, near the top of the cash flow statement, is operating cash flow — real cash from running the business. Note one thing about that line: in almost every filing, the interest already paid to lenders has been taken out of it. Hold that thought; it matters in a moment.

One subtraction out, one add-back in

Operating cash flow isn't free yet — a business must spend to maintain and grow its assets. That spending is capital expenditure (capex), and it comes straight out.

Then the add-back. We're building the firm-level pool (FCFF), the cash belonging to lenders and owners together — and the reported operating cash flow has already handed the lenders their interest. To put the whole pool back together you add that interest back. But only the part the company actually bore: interest is tax-deductible, so paying it shaved the tax bill. Add it back after tax — the interest times (1 − tax rate). So:

Free cash flow to the firm ≈ operating cash flow + after-tax interest paid − capital expenditure

This is the number that is genuinely available to hand to the people who financed the company. It's why a profitable company that must constantly rebuild expensive factories can be worth less than a boring one that prints cash with almost no capex.

(If you skip the add-back you haven't produced a firm-level figure at all — you've produced an equity-level one, cash already net of the lenders' cut. Discount that at a firm-level rate and subtract net debt on top, and you charge the lenders twice. The next unit's whole machinery assumes the firm-level number.)

A worked figure

Say a company reports:

• Operating cash flow: €500 (already net of interest paid)
• Interest paid: €40, at a tax rate of 25%
• Capital expenditure: €180

Add the interest back after tax — €40 × (1 − 0.25) = €30 — then take out capex:

€500 + €30 − €180 = €350

That €350 — not the reported net income, which might be €420 or €280 — is the cash a DCF cares about. Do this for several past years and you have a history of free cash flow, the launch pad for a forecast.

Watch for the lumps

One year's free cash flow can be distorted — a big one-off factory build, a tax quirk, a working-capital swing. That's why practitioners look at three to five years and ask what a normal year looks like, rather than trusting a single number. A DCF built on one weird year is a DCF built on sand.

In the data

Data services publish a free cash flow figure ready-made. Here is Apple's, with the lines it is built from:

Read its definition before feeding it to a DCF: it is operating cash flow minus capital expenditure and nothing else, with no after-tax interest added back. That is the equity-level figure of the previous lesson, not the firm-level one being built here. Capital expenditure is also printed as a positive number despite being cash going out, so adding where you should subtract overstates free cash flow by exactly twice the capex, and nothing on the page flags it.

Try it now

1. Check the definition by hand on the table above: does operating cash flow minus capital expenditure equal the published free cash flow, with nothing else in it? Then name which of the two levels from the previous lesson you are holding, and say what would have to be added to reach the other one.
2. Get the sign wrong on purpose, once. Add capital expenditure where you should subtract it, and measure the gap against the published figure. The size of that gap names the mistake exactly, and it is the reason this line is worth a second look every time.
3. For the add-back you need the interest, and the income statement is where it would be:

An em dash on interest expense means the firm-level figure cannot be completed from the statements for this company. Say so rather than substituting zero — zero would quietly claim the company borrows for free. 4. Now the whole recipe, on a filer that does disclose interest. Three years of Verizon, with the interest from the income statement beside the cash flow rows of the same year:

For each year, add the interest back after tax (the effective rate from the last two rows, or a rough 25%), subtract capital expenditures, and line the three years up. 5. In one sentence, describe a "normal" year of free cash flow for that business. One year can be distorted by a factory build or a working-capital swing; the normal number, not the latest one, is what you will grow in the next lesson.