IFRS vs US GAAP: Key Differences for Companies in Nigeria and the US

Nigeria adopted International Financial Reporting Standards, while US companies report under US GAAP. Groups with operations in both countries, Nigerian companies seeking US investors, and US companies acquiring Nigerian businesses all need to understand where the frameworks differ. Having worked with both as a chartered accountant in Nigeria and a CPA in the United States, these are the differences I see cause the most surprises.

Inventory

US GAAP permits the LIFO method; IFRS prohibits it. IFRS also allows reversal of inventory write-downs when conditions improve, which US GAAP does not.

Impairment

IFRS uses a one-step test and allows reversal of impairment losses on most assets other than goodwill. US GAAP uses a different model and generally prohibits reversals for assets held and used.

Property, plant and equipment

IFRS permits a revaluation model and requires significant components to be depreciated separately. US GAAP uses historical cost, and component depreciation is permitted but less common.

Development costs

IFRS requires development costs to be capitalised when specific criteria are met. US GAAP generally expenses research and development, with exceptions such as certain software costs.

Leases

Under IFRS 16, lessees apply a single model with almost all leases on the balance sheet and depreciation plus interest in profit or loss. US GAAP keeps a distinction between finance and operating leases, with straight-line expense for operating leases.

Presentation

IFRS is generally more principles-based and allows more presentation choices, while US GAAP contains more detailed rules and industry guidance, including for oil and gas producers.

A quick comparison

• Inventory: US GAAP permits LIFO; IFRS prohibits it.
• Impairment reversals: IFRS allows reversal of impairment losses on most assets other than goodwill; US GAAP generally prohibits reversals for assets held and used.
• Property, plant and equipment: IFRS allows a revaluation model; US GAAP requires historical cost.
• Development costs: IFRS requires capitalisation when specific criteria are met; US GAAP generally expenses research and development, with some exceptions such as certain software costs.
• Leases: IFRS 16 uses a single model for lessees; US GAAP distinguishes finance and operating leases in the income statement.
• Component depreciation: required under IFRS where parts have different useful lives; permitted but less common under US GAAP.

Why it matters for Nigerian and US groups

Nigerian companies report under IFRS, while US-listed or US-owned groups often consolidate under US GAAP. A Nigerian subsidiary of a US group may therefore prepare IFRS statements locally and US GAAP reporting packages for the parent. Differences in leases, impairment, revaluation and capitalised costs can produce materially different numbers. Finance teams need a mapping of differences, adjustment schedules and controls over the conversion.

Practical tips for dual reporting

• Maintain one ledger with adjustment layers rather than two separate sets of books.
• Document each accounting policy difference and the calculation method.
• Review differences every quarter, not only at year end.
• Train staff on both frameworks and involve auditors early on judgmental areas.

A leader's view: why executives should care

Accounting framework differences can change reported profit, assets and key ratios, which affect covenants, valuations, bonuses and investor perceptions. Executives of groups operating across Nigeria and the United States should understand the main differences affecting their business and ask finance teams to quantify them. A transaction structured without considering both frameworks can produce unexpected results in one set of accounts.

During my time in PwC's National and Technical Accounting Research Office, much of the work involved helping companies apply complex standards consistently and explain the results clearly. The lesson for leaders is straightforward: involve accounting expertise early in major transactions, not after the deal is signed.

Practical advice

Map differences early in any cross-border transaction, build reconciliations into the reporting process, and make sure valuation models and debt covenants are based on the right framework. Surprises in this area usually appear at the worst moment: during due diligence or the first audit.

Common questions

What is the main difference between IFRS and US GAAP?

IFRS is more principles-based and used in over 140 jurisdictions; US GAAP is more rules-based and required for US domestic public companies. Specific differences include LIFO, impairment reversals, revaluation and development costs.

Does Nigeria use IFRS?

Yes. Nigeria adopted IFRS for public interest entities, and the Financial Reporting Council of Nigeria oversees financial reporting standards.