Owner Earnings vs. Free Cash Flow: Buffett's Perspective and Why It Matters

Buffett's definition from the 1986 letter is worth reading in full:

"Reported earnings plus depreciation, depletion, amortization, and certain other non-cash charges, less the average annual amount of capital expenditures for plant and equipment, etc. that the business requires to fully maintain its long-term competitive position and its unit volume."

The operative word is "average." Buffett wasn't interested in what a company spent on capex last year — he wanted to know what it needs to spend, on average, just to stay in place. That's a harder number to find, and it requires judgment. But it's also a more honest number, because actual capex in any given year can be lumpy, inflated by expansion projects, or depressed because a company deferred maintenance it will eventually have to do.

Owner Earnings represent the cash that can genuinely be taken out of a business without degrading its competitive position. Everything else — reported earnings, operating income, even standard FCF — is a proxy for that number. Buffett just decided to build a closer proxy.

Free Cash Flow is calculated the straightforward way: operating cash flow minus capital expenditures. It's what shows up when you pull numbers from a cash flow statement. The formula is clean and consistent across companies, which is exactly why it's so widely used — and also why it has blind spots.

FCF = Operating Cash Flow − Capital Expenditures

The problem is that capex in a given year reflects whatever decisions management made that year. A company that splurged on a new facility shows depressed FCF. A company that deferred maintenance looks artificially healthy. Neither tells you much about the business's underlying ability to generate cash across a full cycle.

The distinction comes down to one decision: which capex number to use.

Neither is universally better. Standard FCF is objective and comparable. Owner Earnings requires you to make a call about what portion of capex is truly maintenance — which most companies don't disclose. You're estimating, and reasonable analysts can disagree. The tradeoff is precision vs. accuracy: FCF gives you a precise number; Owner Earnings aims for a more accurate one.

For many businesses — particularly asset-light ones like software or consumer brands — the gap between Owner Earnings and FCF is small. Capex is modest, fairly stable, and mostly maintenance in nature. In those cases, standard FCF gets you close enough, and the two metrics will be nearly identical.

The gap widens in capital-intensive industries. A utility, a railroad, or a heavy manufacturer has large capex that swings year to year depending on the investment cycle. In a year when a pipeline company rebuilds a compressor station, FCF craters. In a year when nothing major needs replacing, FCF looks exceptional. Neither year tells you much about the business on its own. Owner Earnings — using normalized maintenance capex across the cycle — smooth out those swings and give you a more stable baseline to value the company against.

Growth investing adds another wrinkle. A company aggressively expanding its store base or production capacity will show low FCF because it's spending heavily on growth capex. That spending is economically different from maintenance capex — it's optional, and it should generate returns. Owner Earnings, by stripping out growth capex, let you see what the business earns from its existing asset base separate from its expansion decisions. That's a more useful number when you're trying to assess the quality of the core business, even if you're also excited about the growth.

For a deeper look at what separates high-quality FCF from the kind that looks good on paper but isn't, see assessing free cash flow quality. And if you want to see how Buffett's thinking on FCF thresholds translates into specific yield targets, the advantages of FCF yield post covers the benchmarks he and other concentrated investors have used.