In short
- FCF = OCF − capex: cash the business generates and doesn't need to feed itself.
- Identical profits can hide opposite FCF realities — the capex appetite is the difference.
- Negative FCF is strategy if slowing growth would flip it; pathology if maintenance capex causes it.
- Pair every P/E with an FCF check — owners are paid from F, not E.
After this lesson you can
- Calculate free cash flow from operating cash flow and capital expenditure
- Explain why FCF — not profit — is the cash a valuation ultimately discounts
- Judge negative FCF in context: investment phase versus broken model
The last subtraction
The cash flow lesson celebrated operating cash flow as the honest number. One subtraction remains. Businesses must spend cash to stay in business: replacing machines, maintaining stores, building data centers — capital expenditure (capex). That spending never touches the income ladder directly (it becomes assets, then depreciates), but the cash is genuinely gone. Free cash flow subtracts it: the cash the business generated AND doesn't need to feed itself — free to pay dividends, buy back shares, repay debt, or compound into growth. This is the 'future owner cash' the valuation lesson's principle discounts.
Key point: FCF = the owner's true takeaway. Everything upstream of it is still feeding the machine.
The formula, worked
FCF = Operating cash flow − Capital expenditure
Suppose a company produces $400M of operating cash flow and spends $150M on capex: FCF = 400 − 150 = $250M — an FCF margin of 25% on $1B revenue. Compare its twin reporting the SAME $400M OCF but needing $380M of capex to stay competitive: FCF = $20M. Identical income statements can hide this chasm: one business mints owner cash; the other runs hard to stand still, its 'profits' perpetually recycled into machinery. Refinement worth knowing: analysts separate maintenance capex (staying alive) from growth capex (expanding) — reported capex blends both, so the raw FCF of a heavy investor can understate its mature earning power.
Reading negative FCF honestly
Negative FCF is not a verdict — it is a question with two very different answers. The investment story: a young company deliberately pours cash into growth capex ahead of revenue; negative FCF now, by choice, with unit economics (fat gross margins, improving operating leverage) that promise future harvests. The treadmill story: a mature business whose capex is mostly MAINTENANCE and still swallows its OCF — no choice involved, no harvest coming. The separator: could this business turn FCF-positive by merely slowing growth? If yes, the burn is strategy. If capex is obligatory and FCF stays negative, the business model itself is the problem.
Common trap: profit-rich, cash-poor 'value'
Screens love companies with low P/E — but P/E's E is accounting profit, and capital-hungry businesses can report handsome E while generating no F. A company earning $2 EPS that must reinvest every dollar to keep its plants competitive delivers owners nothing — its true multiple on OWNER cash is far higher than its P/E advertises. This is why seasoned investors pair every P/E with an FCF check (price ÷ FCF, the 'cash P/E'), and why the durable compounders of history have tended to be FCF machines, not just EPS printers.
Practise what you just read
Take this lesson's quiz and review cards in the app, then try the idea with virtual money in paper trading. Free account, no card.
Education only, not investment advice. Examples are illustrative. Read the full disclaimer