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    German GAAP to US GAAP: What Changes When a German Company Raises US Capital or Is Acquired

    November 6, 2026

    Converting German GAAP to US GAAP is a re-measurement of the HGB accounts, not a reformatting exercise. The numbers usually change in seven areas: provisions, pensions, inventory write-downs, development costs and goodwill, deferred tax, revenue under ASC 606 and leases under ASC 842. A German company needs this conversion when it takes on US investors, is acquired by a US parent or prepares for a US listing, and the work is different from the HGB to IFRS conversions that most German advisors handle. The US auditor will expect a conversion matrix, technical memos on the judgment areas, journal entries that trace to the matrix and a US GAAP trial balance.

    Key takeaways

    • HGB is designed for creditor protection and prudence, and many German companies align it with the tax return. US GAAP is designed for investors and has no link to tax.
    • HGB provisions that are not liabilities under ASC 450, such as deferred maintenance and most provisions for losses on pending contracts, reverse on conversion.
    • Pension obligations are remeasured with a discount rate at the measurement date instead of the HGB ten-year average Bundesbank rate, and pre-1987 and indirect pension commitments come onto the balance sheet.
    • Development costs capitalized under HGB are generally expensed under ASC 730, and deferred tax is recalculated without the HGB options and five-year loss limit.
    • If your statutory auditor, or a firm in its network, will audit US GAAP financial statements filed with the SEC, or you are a public-interest entity, independence rules prevent it from preparing them.

    Why HGB and US GAAP produce different numbers

    HGB is designed to protect creditors. Its prudence principle (Vorsichtsprinzip, § 252(1) no. 4 HGB) requires foreseeable risks and losses to be recognized at the balance sheet date, while profits are recognized only once they are realized. The result is conservative equity and, in many companies, hidden reserves: assets carried below their value and provisions measured at the upper end of the range.

    HGB is also closely tied to tax. Under the authoritative principle (Maßgeblichkeitsprinzip, § 5(1) EStG), the HGB accounts are the starting point for the tax balance sheet, and many German companies choose HGB options that match the tax treatment so that one set of accounts serves both purposes. The Accounting Law Modernisation Act of 2009 (BilMoG) removed the reverse link (umgekehrte Maßgeblichkeit), so purely tax-driven values are no longer permitted in HGB accounts, but the practice of aligning the two remains common.

    US GAAP is designed to give investors decision-useful information. It has no link to the tax return and does not favor conservative measurement for its own sake. Each difference below follows from that change in purpose.

    The German GAAP to US GAAP differences that change the numbers

    Provisions

    HGB requires provisions for uncertain liabilities and for expected losses from pending transactions (Drohverlustrückstellungen). It also requires two provisions with no obligation to a third party: maintenance deferred from the financial year and carried out within the first three months of the next year (or overburden removal carried out in the next year), and warranties given without a legal obligation (§ 249(1) HGB). No other provisions are permitted (§ 249(2) HGB), because BilMoG abolished the broader options for expense provisions (Aufwandsrückstellungen). Provisions are measured at the settlement amount required under prudent commercial judgment, including expected price and cost increases, and provisions due in more than one year are discounted at a seven-year average rate published by the Deutsche Bundesbank (§ 253(1) and (2) HGB).

    US GAAP differs in recognition and in measurement:

    • Recognition. ASC 450 requires an accrual only when a loss is probable, meaning likely to occur, and can be reasonably estimated. Deferred maintenance provisions have no obligation behind them and reverse.
    • Losses on pending contracts. US GAAP generally does not allow losses on executory contracts to be recognized before the costs are incurred. Most HGB provisions for expected losses on pending transactions therefore reverse, and the matrix should identify any contract covered by a specific US GAAP loss rule.
    • Measurement. When no amount in a range is a better estimate than any other, ASC 450 accrues the low end of the range. Discounting is a policy choice permitted only when the amount and timing of payments are fixed or determinable, so the HGB Bundesbank average rates do not carry over.

    The reversal of these provisions increases equity at the opening balance sheet date and moves the expense into the periods in which the costs are incurred.

    Pension obligations

    HGB discounts pension obligations at the average market rate of the past ten years, published monthly by the Bundesbank, and permits a flat rate based on an assumed remaining term of 15 years (§ 253(2) HGB). Since BilMoG, the HGB settlement amount includes expected salary and pension increases, so the salary trend is usually not the source of the difference. The differences are:

    • Discount rate. ASC 715 uses the rate at which the obligation could be effectively settled at the measurement date, which companies usually derive from high-quality fixed-income investments with matching durations. A ten-year average moves slowly and can differ from a current market rate in either direction.
    • Actuarial gains and losses. HGB recognizes them in profit or loss. ASC 715 allows them to be recognized in other comprehensive income and amortized into pension cost when they exceed a corridor, or recognized immediately under an accounting policy.
    • Unrecognized legacy obligations. HGB does not require provisions for direct pension commitments acquired before 1 January 1987 or for indirect obligations, for example through a support fund (Unterstützungskasse); corporations disclose the unrecognized amount in the notes (Art. 28 EGHGB). ASC 715 recognizes the funded status of defined benefit plans, so these obligations come onto the balance sheet.

    Inventory

    Both frameworks allow FIFO and LIFO (§ 256 HGB) and weighted average cost (§ 240(4) HGB), so the cost formula is rarely the issue. The differences are in write-downs:

    • HGB requires current assets to be written down to a lower market price or lower attributable value at the balance sheet date (§ 253(4) HGB), and requires the write-down to be reversed once the reason for it no longer applies (§ 253(5) HGB).
    • ASC 330 measures FIFO and average-cost inventory at the lower of cost and net realizable value, and LIFO and retail-method inventory at the lower of cost or market (ASU 2015-11). A year-end write-down becomes the new cost basis and is not reversed in later years (ASC 330-10-35-14).

    The conversion re-tests HGB write-downs against net realizable value and removes HGB reversals that US GAAP does not allow.

    Development costs, goodwill and fixed assets

    • Development costs. HGB permits, but does not require, capitalization of self-created intangible fixed assets, and prohibits capitalization of self-created brands, print titles, publishing rights and customer lists (§ 248(2) HGB). US GAAP expenses research and development as incurred (ASC 730), with separate capitalization rules for internal-use software (ASC 350-40) and software to be sold (ASC 985-20). Development costs capitalized under HGB generally reverse unless they qualify under those software rules.
    • Goodwill. HGB amortizes goodwill over its useful life, or over ten years when the useful life cannot be reliably estimated (§ 253(3) HGB). Under US GAAP, public business entities do not amortize goodwill and test it for impairment (ASC 350), while private companies may elect to amortize it over ten years or less.
    • Fixed assets. HGB requires a write-down for an impairment expected to be permanent and a reversal when the reason no longer applies (§ 253(3) and (5) HGB). ASC 360 tests long-lived assets for recoverability when events indicate that the carrying amount may not be recoverable, and does not allow an impairment loss on assets held and used to be reversed. Useful lives chosen to match German tax depreciation tables, and low-value assets expensed or pooled under tax rules, need to be reassessed against actual use.

    Deferred tax

    Since BilMoG, HGB also uses a balance sheet concept: deferred taxes arise from differences between the HGB and tax carrying amounts of assets and liabilities (§ 274 HGB). The differences from ASC 740 are in recognition:

    • HGB requires a net deferred tax liability but makes a net deferred tax asset optional, and many companies do not recognize one.
    • HGB counts tax loss carryforwards only to the extent they are expected to be used within the next five years. ASC 740 has no fixed period: it recognizes all deferred tax assets and reduces them by a valuation allowance when it is more likely than not that some portion will not be realized.
    • Small corporations are exempt from § 274 HGB (§ 274a HGB) and may have no deferred tax accounting at all. ASC 740 has no such exemption.

    Every other conversion adjustment creates its own temporary difference, so deferred tax is recalculated after all other adjustments are booked.

    Revenue under ASC 606 and leases under ASC 842

    HGB has no comprehensive revenue standard. It applies the realization principle: profits are recognized only when they are realized at the balance sheet date (§ 252(1) no. 4 HGB). ASC 606 requires a five-step model: identify the contract, identify the performance obligations, determine the transaction price, allocate it to the performance obligations, and recognize revenue when or as each obligation is satisfied. Plain product sales often give the same result under both frameworks. Bundled contracts, subscriptions, software licenses, variable consideration and costs to obtain a contract usually do not, and they need a technical memo.

    HGB recognizes an asset in the balance sheet of its economic owner (§ 246(1) HGB), and lessees in practice apply the classification criteria of the German tax leasing decrees (Leasingerlasse), so most leases stay off the lessee’s balance sheet. ASC 842 brings nearly all leases onto the balance sheet as a right-of-use asset and a lease liability. The only exemption is an election for leases of 12 months or less; there is no low-value exemption. Lessees still classify leases as finance or operating, and an operating lease keeps a single straight-line lease cost in the income statement. For a company with significant property, vehicle or equipment leases, the gross-up changes reported assets, liabilities and leverage ratios.

    What your finance team needs to give the US auditor

    A US auditor tests documented adjustments, not a final adjusted number. The core deliverables are:

    • A conversion matrix that sets out each HGB accounting policy, the US GAAP target policy, the difference and the adjustment required, category by category.
    • Technical accounting memos on the judgment areas, typically revenue (ASC 606), leases (ASC 842) and, where relevant, share-based compensation or business combinations.
    • Conversion journal entries, split between opening balance sheet entries and entries for each later period, each referenced to a line in the matrix.
    • A US GAAP trial balance that reconciles to the HGB statutory ledger, so the auditor can trace every difference.

    The auditing standards depend on the purpose: PCAOB standards for financial statements filed with the SEC, and generally AICPA standards for a private company audit for US investors or lenders. For a fuller list, see what your auditor needs from a GAAP conversion. If the books are kept in DATEV, the chart of accounts also has to be remapped; see DATEV to US GAAP.

    Why your German statutory auditor is not the right resource

    Your Wirtschaftsprüfer knows your HGB accounts and your business, but auditor independence rules limit what the firm can do on a US GAAP conversion:

    • SEC rules. An accountant is not independent if it prepares an audit client’s financial statements that are filed with the SEC or that form the basis of financial statements filed with the SEC (Regulation S-X Rule 2-01(c)(4)(i)). The rule covers the audit firm’s associated entities, including those outside the United States (Rule 2-01(f)(2)), so it reaches a German network firm that audits the subsidiary of an SEC registrant.
    • EU Audit Regulation. For a German public-interest entity, the statutory auditor and its network may not provide bookkeeping or prepare accounting records and financial statements for the entity, its parent or its EU subsidiaries (Article 5, Regulation (EU) No 537/2014).

    Independence aside, a statutory audit team tests compliance with HGB. It does not routinely build ASC 606 and ASC 842 positions from first principles. The conversion is a separate technical project that produces the documentation the auditor then tests.

    Scope the conversion before the transaction timetable is set

    An HGB to US GAAP conversion reverses prudence-driven provisions, rebuilds pensions and deferred tax on a US basis, and applies US GAAP revenue, lease and intangible asset rules that have no HGB equivalent. Companies that complete it on schedule run it as a documented project with a conversion matrix and supporting memos. For reference, a UK consumer goods group with a German subsidiary converting UK GAAP and HGB to US GAAP, including preparation of the US GAAP trial balance, took about eight weeks. The GAAP conversion cost post explains what drives the fee.

    If a US investment, acquisition or listing is planned, see how a GAAP conversion engagement is scoped and start the matrix before due diligence begins.