Amazon's FY2025 free cash flow was $7.7B. Or $6.1B. Or −$11.8B.

If you looked up Amazon’s 2025 free cash flow at three different places this week, there is a good chance you got three different numbers. Not slightly different — different by nearly twenty billion dollars, and different in sign.

None of those sources is necessarily wrong. Free cash flow is not a GAAP measure. There is no line on the cash flow statement that says “free cash flow,” and no rule that says what belongs in it. Every publication picks a definition, most never say which one, and the gap between the common choices is now wide enough to flip a company from cash-generative to cash-consuming.

Here is the same fiscal year, from the same filing, under three definitions that are all in ordinary use.

Amazon FY2025, three ways

A.  Free cash flow  =  operating cash flow  −  purchases of property and equipment
B.  Free cash flow  =  A  −  principal repayments of finance leases
C.  Free cash flow  =  A  −  stock-based compensation

The spread between the highest and lowest figure is $19.5 billion. Definition A says Amazon generated cash. Definition C says it consumed it. Both are computed from the same three lines of the same audited statement.

The SEC says this out loud

This is not a loophole anyone is exploiting. The regulator’s own staff guidance says it plainly. In Question 102.07 of the Division of Corporation Finance’s non-GAAP interpretations, the staff notes that free cash flow “does not have a uniform definition and its title does not describe how it is calculated” — and therefore that a clear description of the calculation should accompany the measure wherever it appears.

The same passage carries a second warning that matters here: free cash flow should not be presented in a way that implies it is cash available for discretionary use, because many companies have mandatory obligations that the measure does not deduct.

That is the whole problem in one sentence. Definition A treats finance-lease principal as optional. For a company that leases much of its warehouse and data-centre footprint, it is not optional at all.

What each definition is actually arguing

Definition A is the default, and the one the SEC’s guidance describes as typical. It asks a narrow question: after paying to maintain and expand the asset base, how much operating cash is left? It ignores how those assets were financed.

Definition B closes that gap. If a company buys a data centre it shows up in capex; if it leases the same data centre under a finance lease, the principal repayment shows up in financing activities and definition A never sees it. Amazon’s own investor materials have long deducted these. For Amazon in FY2025 the adjustment is modest — $1,557M — but it has not always been: the same line was $11.2B in FY2021, when the lease-financed build-out was at its peak.

Definition C is the most aggressive and the most contested. Stock-based compensation is a real cost that is settled in shares rather than cash, so it is added back in operating cash flow. Analysts who deduct it argue that the cost is borne by existing shareholders through dilution and should not vanish just because no cash moved. Analysts who do not deduct it argue that dilution is already visible in the share count, and subtracting it here double-counts.

We are not adjudicating that. The point is narrower: whichever you prefer, a publication that reports a free cash flow figure without saying which one it used has told you very little.

The other three, same test

Amazon is the only one of the four where the choice of definition changes the sign. The others stay positive under all three — but the spread is still large enough to matter. Alphabet’s range is $25.0B wide. Meta’s is $20.4B wide. Those are not rounding differences; they are larger than the annual free cash flow of most companies in the S&P 500.

The reason the four diverge is visible in one ratio.

At 94.5%, Amazon has almost no buffer. A definition that deducts one more item is a definition that produces a negative number — which is why the three answers diverge for Amazon and not for the others. It is not that Amazon’s accounting is unusual. It is that its margin for definitional disagreement has been spent.

Amazon’s most recent twelve months are already negative

The FY2025 figures above end in December 2025. The company’s Form 10-Q for the quarter ended June 30 2026 presents a trailing-twelve-month cash flow statement, and by that window the question is no longer definitional.

Operating cash flow                    $161,403M
Purchases of productive assets        −$173,028M
───────────
Definition A                           −$11,625M
Finance-lease principal repayments      −$1,599M
───────────
Definition B                           −$13,224M

Under the most generous of the three definitions, the trailing year is negative $11.6 billion. No adjustment is required to get there.

Three ways this goes wrong before you even start

Everything above assumes you pulled the right numbers. In practice, the standardised data most tools are built on will hand you the wrong ones in at least three ways.

Amazon does not use the standard capex tag

The XBRL element almost every screener reads for capital expenditure is PaymentsToAcquirePropertyPlantAndEquipment. Amazon last reported under that tag in 2017. Since then its capital spending has been filed as PaymentsToAcquireProductiveAssets.

Query the standard tag and you do not get an error. You get a value from 2017, or nothing at all — and “nothing at all” becomes zero somewhere downstream, which turns the most capital-intensive company in this table into the least. This is the same class of failure as the debt figure that was reported 4,874x too small.

Microsoft’s year does not line up with anyone else’s

Microsoft’s fiscal year ends June 30. Its FY2026 covers July 2025 to June 2026. Alphabet, Amazon and Meta all closed FY2025 on December 31 2025. Putting these four in one column labelled “2025” or “latest year” compares a period that includes the first half of 2026 against periods that do not — during a stretch when capital spending was rising quickly. We have labelled each row with its own fiscal year above rather than pretend otherwise.

Quarterly filings carry annual-looking numbers

Not every company files a 10-Q at all — a foreign private issuer files a 20-F and 6-Ks instead, and the quarterly figures land in a different place with different accompanying detail.

Amazon’s 10-Q reports trailing-twelve-month cash flows. Those rows span 365 days, so any filter that keeps “annual” periods will accept them — and a routine that buckets values by the reporting API’s fiscal-year field, rather than by the period end date, will file a July-to-June trailing window under the wrong calendar year. We hit exactly this while assembling this article: an early draft had Amazon’s FY2025 operating cash flow at $121.1B, which is the trailing year ended June 2025, not the fiscal year ended December 2025.

What would make this wrong

• The figures are as-filed and can be restated. Every number here is traceable to the accession numbers listed at the bottom of this page, taken on the date noted. Issuers revise prior-period figures, and when they do, the value in a newer filing supersedes the one here.
• Definition C is a choice, not a standard. Presenting it alongside A and B is meant to show the range of published practice, not to endorse deducting stock-based compensation.
• Finance-lease principal is not the only financing-shaped obligation. Companies also report financing obligations for build-to-suit and similar arrangements. Deducting those as well would push every figure in the B column lower. We deducted only the line that is separately tagged and directly comparable across all four companies.
• A single ratio is not a verdict on a business. Capex at 94.5% of operating cash flow says what a company spent, not whether the spending will earn a return. This article makes no claim about the latter.

Check it yourself

Each filing is linked below, and each figure comes from the consolidated statements of cash flows inside it. The three lines you need are operating cash flow, purchases of property and equipment (or productive assets), and principal repayments of finance leases. The subtraction is the whole method.

If you find a figure here that does not match the filing, tell us and it will be corrected on the article and on the corrections log, with the date.