GAAP vs non-GAAP earnings: how adjusted numbers are built

Every US public company reports its profit under GAAP, the generally accepted accounting principles. Many also publish a second, non-GAAP version: "adjusted EPS", "adjusted EBITDA", "core earnings". The adjusted number leaves out items management considers unusual or not part of running the business, and it is often the number in the headline.

Neither number is "the truth". GAAP applies the same rules to everyone, including to events that will never happen again. Non-GAAP removes noise but lets management decide what counts as noise. The skill is reading the reconciliation between the two, which SEC rules require, and judging each adjustment on its merits.

This page explains the rules, then rebuilds a real reconciliation: Apple's fourth quarter of fiscal 2025, where diluted EPS of $1.85 was "up 13 percent year over year on an adjusted basis" and up 91% on a GAAP basis.

What GAAP is

US GAAP is the body of accounting standards set by the Financial Accounting Standards Board (FASB) and collected in its Accounting Standards Codification. The SEC recognizes the FASB as the standard setter for US public companies, so the audited financial statements in every 10-K and 10-Q follow GAAP. (Most of the rest of the world uses IFRS; foreign companies filing with the SEC may use IFRS instead.)

GAAP's strength is consistency. A $10 billion tax charge is recorded the same way whether it is routine or a once-in-a-decade event, and an auditor checks that the rules were followed. Its weakness is the same: it does not distinguish the recurring from the extraordinary. That gap is what non-GAAP measures try to fill.

The SEC rules for non-GAAP measures

Non-GAAP figures are legal, but they are regulated. After a wave of creative "pro forma" earnings around 2001, the SEC adopted Release 33-8176, Conditions for Use of Non-GAAP Financial Measures, issued January 22, 2003 and effective March 28, 2003. It created two sets of rules.

Regulation G (17 CFR 244.100) applies whenever a company publicly discloses a non-GAAP financial measure, in a filing, a press release, a slide deck or a call. The company must present the most directly comparable GAAP measure and a reconciliation that is quantitative for historical measures. It also may not present a non-GAAP measure that, with its accompanying information, is misleading by stating an untrue material fact or omitting one.

Regulation S-K Item 10(e) (17 CFR 229.10(e)) applies to SEC filings and is stricter. On top of the reconciliation, the GAAP measure must be presented with equal or greater prominence. Item 10(e) also forbids, among other things:

• adjusting a performance measure to remove items labelled non-recurring, infrequent or unusual when a similar item is reasonably likely to recur within two years or occurred in the prior two years;
• presenting non-GAAP measures on the face of the GAAP financial statements or in their notes;
• using titles that are the same as, or confusingly similar to, GAAP titles.

The SEC staff's Compliance and Disclosure Interpretations (C&DIs) on non-GAAP measures, last updated December 13, 2022, explain how the staff reads these rules. Three are worth knowing:

• Question 100.01: excluding normal, recurring cash operating expenses from a performance measure can be misleading even though no rule names it. The staff treats an expense as recurring if it occurs repeatedly or occasionally, including at irregular intervals.
• Question 100.04: adjustments that change GAAP's recognition or measurement principles, such as speeding up revenue that GAAP recognizes over time, are "individually tailored" accounting and can be misleading.
• Question 102.10: examples of a non-GAAP measure being more prominent than its GAAP counterpart include putting it first, omitting the GAAP figure from a headline, describing it as a "record" without an equally prominent GAAP description, or showing charts of the non-GAAP figure alone.

Apple's real reconciliation

On September 10, 2024, the European Court of Justice confirmed the European Commission's 2016 State Aid decision against Ireland's tax treatment of two Apple subsidiaries. In the fourth quarter of fiscal 2024, Apple recorded a one-time income tax charge. Its 10-K describes the charge as $10.2 billion, net.

The charge sat entirely in the provision for income taxes. Revenue, gross margin and operating income were untouched. A year later, Apple's Q4 fiscal 2025 release reconciled the prior-year quarter so the comparison would exclude it.

Why "up 13%" and "up 91%" are both true

Apple's Q4 fiscal 2025 diluted EPS was $1.85. Against the GAAP prior-year $0.97, that is $1.85 ÷ $0.97 − 1 = +90.7%. Against the adjusted $1.64, it is $1.85 ÷ $1.64 − 1 = +12.8%, which the release rounds to "up 13 percent". Net income tells the same story: $27,466M was up 86.4% on GAAP and 9.9% on the adjusted base.

Here the adjusted figure is the less flattering one. Apple used non-GAAP to stop a one-time hit from making the next year look spectacular. The release still stated the GAAP EPS of $1.85 in its headline paragraph, pointed to the reconciliation in a footnote, and printed the full GAAP statements. The footnote also explains why the company believes the adjusted view helps comparison, and says the figures "should not be viewed as a substitute" for GAAP.

Is this a good adjustment? By most tests, yes: the item is large, clearly identified, non-operating, tied to a single court ruling, and it is the only line in the reconciliation. Note it is also not entirely gone from later years: the 10-K shows a $486 million State Aid benefit in the fiscal 2025 tax reconciliation, which Apple did not adjust out.

Common adjustments at other companies

Apple's reconciliation has one line. Many companies have a dozen. These categories show up again and again; each needs its own judgment.

Stock-based compensation is the biggest and most debated. At Apple it was $12,863 million in fiscal 2025 cash-flow terms, 11.5% of net income. Apple does not exclude it, which is why its GAAP and adjusted EPS were identical in fiscal 2025. Many software companies do exclude it, and their adjusted margins can be far above GAAP margins as a result.

Red flags in a reconciliation

• The same "one-time" item every year. Restructuring in five consecutive years is a cost of doing business. Item 10(e) bars calling such items non-recurring in filings.
• Only costs go out, never gains. If a gain on a sale stays in and a loss on a sale comes out, the adjustments are one-sided.
• Ordinary cash expenses excluded. Rent, marketing, customer-acquisition or "launch" costs are running the business; C&DI 100.01 flags them.
• A growing gap. Track GAAP and adjusted EPS together over several years. A gap that widens every year deserves a reason.
• New definitions. Watch for a measure whose definition changes from one year to the next, or one that has a GAAP-sounding name.
• Adjusted figures without the cash. Compare adjusted earnings with cash from operations, the approach on the Quality of earnings: accruals, cash conversion and red flags page.

GAAP, non-GAAP and related measures

EBITDA and free cash flow are non-GAAP measures too when a company publishes them, so the same reconciliation requirement applies to them.

How Finabase does it

Finabase shows GAAP figures. The Financials tab carries reported net income and basic and diluted EPS by quarter and by year, so Q4 fiscal 2024 shows the $0.97 that includes the tax charge (labelled "Q3 2024" because Finabase names columns by calendar quarter). Finabase does not build adjusted figures or reconciliations; for those, open the company's earnings release on EDGAR.

The Earnings tab compares reported EPS with the consensus estimate. Those comparisons come from the data provider, and providers often compare on the adjusted basis analysts forecast. When a company reports large adjustments, check which basis a surprise uses before reading it.

Frequently asked questions

Is non-GAAP earnings legal?

Yes. US companies may publish non-GAAP measures, but Regulation G requires the comparable GAAP figure and a quantitative reconciliation, and Item 10(e) adds equal-or-greater prominence and specific prohibitions in SEC filings.

Which is better, GAAP or adjusted EPS?

Neither on its own. GAAP is consistent and audited but mixes one-off events with the trend; adjusted EPS can show the trend more clearly but reflects management's choices. Read both and judge every adjustment in the reconciliation.

Why did Apple report adjusted EPS only for fiscal 2024?

Because only fiscal 2024 had the item Apple chose to exclude: the one-time $10.2 billion State Aid tax charge. With no comparable item in fiscal 2025, GAAP and adjusted EPS were the same.

Do analysts forecast GAAP or non-GAAP earnings?

Usually the adjusted figure, following each company's own definition, though practice varies by data vendor and company. That is why reported-versus-estimate comparisons can differ from GAAP growth rates.

Summary

GAAP earnings follow one set of audited rules; non-GAAP earnings remove items management calls unusual. SEC Regulation G (2003) requires every public non-GAAP figure to be reconciled to GAAP, and Item 10(e) adds equal-or-greater prominence and bans on misleading adjustments. Apple's reconciliation is a clean example: one $10,246 million tax charge lifts Q4 fiscal 2024 EPS from $0.97 to $1.64 and full-year EPS from $6.08 to $6.75, turning 91% growth into 13%. Judge any company's adjustments by whether they recur, whether they are one-sided, and whether the cash agrees.