Jun 5, 2026· sec · fundamentals · valuation

How to calculate free cash flow margin

Free cash flow margin is free cash flow divided by revenue. Here's the formula, what counts as a good margin, and how to track it quarter by quarter.

Free cash flow margin answers a simple question: of every dollar a company brings in as revenue, how much ends up as cash it can actually do something with? It's one of the cleanest measures of business quality, because unlike profit margin it's hard to flatter with accounting choices.

The formula

Free cash flow margin = free cash flow ÷ revenue, expressed as a percentage. Free cash flow itself is operating cash flow minus capital expenditure (FCF = CFO − CapEx); see how to calculate free cash flow from a 10-K for where those two inputs sit in the cash flow statement.

What counts as a good margin

There's no universal threshold, but a durable double-digit FCF margin is a strong sign — it means the business turns sales into cash without constant heavy reinvestment. Software and asset-light companies routinely clear 20-30%; capital-intensive businesses run far lower, and that's expected. Judge it against the company's own trend and its peers.

Track it per quarter

Both inputs — free cash flow and revenue — come straight from a company's SEC filings. Finterm is a free SEC EDGAR viewer that computes FCF = CFO − CapEx on the wire from companyfacts and shows it next to revenue per quarter, so the margin trend is easy to eyeball without exporting anything.

warnFree cash flow is lumpy quarter to quarter — working-capital swings and one-off CapEx can push a single quarter's margin well above or below the real run rate. Use a trailing-twelve-month figure, or average several quarters, before drawing conclusions.

FCF margin vs. net income margin

Net income is subject to accruals — revenue can be recognised before cash arrives, expenses can be deferred, and depreciation spreads a cash outflow across years. FCF margin is harder to manage through accounting choices: you either collected the cash or you didn't, and you either spent it on CapEx or you didn't. A company whose FCF margin consistently runs below its reported net income margin may be collecting revenue slowly (growing receivables), paying suppliers quickly (deteriorating working capital), or has CapEx running well above the depreciation line. All three are worth investigating.

How FCF margin compresses

Two things compress FCF margin: CapEx increases and working capital deterioration. Rising CapEx isn't automatically bad — a company investing ahead of planned revenue growth is behaving rationally, and the margin should recover as revenue scales into the new capacity. Working capital deterioration is a different signal: customers paying slower, inventory building up, or the company being squeezed by suppliers. If margins are compressing and CapEx is flat, the working capital section of the cash flow statement is usually where the explanation lives.