Current and Deferred Tax: Temporary Differences and Recognition

In accounting, current and deferred tax are the two components that together make up a company’s total income tax expense. Current tax is what a company owes the government for this year’s taxable income under the tax code. Deferred tax captures the future tax consequences of transactions that already sit on this year’s financial statements but won’t reach the tax return until a later period. The split exists because financial accounting and the tax code frequently disagree about when to count revenue and expenses, and deferred tax accounting keeps the income statement from whipsawing as a result.

How Current Tax Works

Current tax begins with taxable income, which is computed under Internal Revenue Code rules rather than under financial accounting standards. A company takes its gross revenue, subtracts the deductions the tax code allows, and applies the statutory rate to what remains. For U.S. corporations, the federal rate is a flat 21 percent.1Office of the Law Revision Counsel. 26 USC 11 – Tax Imposed Most states add a corporate income tax on top, with rates ranging from zero to roughly 11.5 percent depending on where the company operates.

Under both U.S. GAAP (ASC 740) and international standards (IAS 12), current tax is measured using rates that have been enacted by the balance sheet date.2IFRS. IAS 12 Income Taxes The result lands on the balance sheet as either a liability (tax still owed) or an asset (a refund expected). Underpayments accrue interest at the federal short-term rate plus three percentage points, compounded daily.3Office of the Law Revision Counsel. 26 USC 6621 – Determination of Rate of Interest

Why Deferred Tax Exists

Financial accounting and the tax code often place the same transaction in different periods. A company might recognize a sale, an expense, or an asset write-down on this year’s income statement while the tax effect doesn’t appear on the return until years later. Without deferred tax accounting, the reported tax rate would jump around from year to year for reasons that have nothing to do with the real economics of the business.

Deferred tax fixes this by matching the tax effect of a transaction to the same period as the transaction itself. When a company writes off equipment faster on its tax return than on its books, it pays less tax now but will pay more later once the accelerated deductions run out. The deferred tax entry records that future obligation today. If a company instead recognizes an expense on its books before the tax code allows the deduction, the future tax benefit is booked now as an asset. Either way, the income statement reflects the full tax cost of operating during the period, not just the cash amount currently due.

Temporary Differences

Temporary differences drive deferred tax. They arise whenever an asset or liability has one carrying value on the balance sheet and a different value for tax purposes, and the gap will eventually close. Taxable temporary differences produce deferred tax liabilities. Deductible temporary differences produce deferred tax assets.

Accelerated Depreciation

The textbook example of a taxable temporary difference is accelerated depreciation. The federal tax code allows most tangible property to be depreciated under the Modified Accelerated Cost Recovery System, which front-loads deductions using a 200 percent declining-balance method for many asset classes.4Office of the Law Revision Counsel. 26 USC 168 – Accelerated Cost Recovery System Financial statements often spread the same cost evenly over the asset’s useful life using straight-line depreciation. In the early years, the tax deduction outruns the book expense and the current tax bill drops. That savings is not permanent; the deferred tax liability on the balance sheet records the extra tax the company will owe in later years when the tax deductions shrink below the book expense.

Warranty Reserves

Warranty obligations create a deductible temporary difference. A company estimates its warranty costs and records the expense on the income statement in the year the product is sold. The tax code doesn’t allow a deduction until economic performance occurs, meaning the repair work is actually done or the parts are actually provided.5Office of the Law Revision Counsel. 26 USC 461 – General Rule for Taxable Year of Deduction Current tax is higher than book income would suggest, and a deferred tax asset sits on the balance sheet representing the benefit that will materialize when the repairs happen.

Advance Payments

Advance payments for services work the same way. A business that collects a year of subscription fees upfront generally includes the full amount in taxable income right away.6eCFR. 26 CFR 1.451-8 – Advance Payments for Goods, Services, and Certain Other Items Financial accounting rules recognize the revenue gradually as the service is delivered. The mismatch creates a deferred tax asset, because tax has already been paid on income the books haven’t yet recognized.

Foreign Research Costs

Research spending is a more recent source of temporary differences. Under Section 174A, enacted as part of the One Big Beautiful Bill Act of 2025, domestic research and experimental costs can once again be fully deducted in the year incurred for tax years beginning after December 31, 2024. Foreign research costs, however, must still be capitalized and amortized over 15 years. If a company’s financial statements expense all R&D immediately regardless of location, the foreign portion produces a deductible temporary difference, because the book expense hits today while the tax deduction trickles in over the amortization period.

Permanent Differences Are Not Deferred Tax

Not every gap between book income and taxable income eventually closes. Permanent differences arise when revenue or expenses appear on the financial statements but will never appear on the tax return, or the reverse. Because they never reverse, they don’t generate deferred tax entries at all. They simply push the company’s effective tax rate above or below the 21 percent statutory rate.

Common permanent items include:

Recognizing Deferred Tax Assets and Liabilities

A deferred tax liability is recognized for essentially every taxable temporary difference. If a company has already taken a tax benefit it hasn’t earned under book accounting, the future payback is virtually certain, so the liability goes on the balance sheet. IFRS has narrow exceptions for certain initial recognition situations, but the general rule is recognition.2IFRS. IAS 12 Income Taxes

Deferred tax assets face a higher bar. A company records a deferred tax asset only when it expects to earn enough taxable income in the future to actually use the deduction or credit. Under U.S. GAAP, the asset is booked in full and then reduced by a valuation allowance if it’s more likely than not (greater than 50 percent probability) that some or all of the benefit won’t be realized. Under IFRS, the asset is simply written down to the amount considered probable.

The valuation allowance weighs all available evidence. Positive evidence includes strong recent profitability, secured contracts, and existing taxable temporary differences that will reverse and generate future taxable income. Negative evidence includes cumulative losses in recent years, a history of tax benefits expiring unused, or expected losses in the near term. When significant negative evidence exists, overcoming it requires substantial objective positive evidence rather than optimistic forecasts. Auditors scrutinize this judgment closely.

Net Operating Loss Carryforwards

For a business that has been through a rough stretch, the largest deferred tax asset is often the net operating loss carryforward. Current federal law allows a taxable loss to be carried forward indefinitely to offset future taxable income. Losses arising in tax years beginning after 2017 can offset only 80 percent of taxable income in any given future year, so an NOL carryforward can never zero out a tax bill entirely.10Office of the Law Revision Counsel. 26 USC 172 – Net Operating Loss Deduction

The associated deferred tax asset is the loss amount multiplied by the expected future tax rate. Ten million dollars in federal NOLs at 21 percent produces a $2.1 million deferred tax asset, assuming the company will earn enough to use it. If profitability looks doubtful, a valuation allowance chips away at that figure. The size of that allowance is often watched as a signal of whether management genuinely believes future profits are on the horizon.

How the Two Interact in Practice

Consider a company that buys $5 million in equipment, depreciates it over three years for tax purposes using MACRS, and over seven years on a straight-line basis for book purposes.4Office of the Law Revision Counsel. 26 USC 168 – Accelerated Cost Recovery System In year one, tax depreciation far exceeds book depreciation. The current tax bill drops because taxable income is lower, but a deferred tax liability grows to reflect the taxes that are merely postponed. By year four, tax depreciation has been fully claimed while book depreciation continues. Now taxable income exceeds book income, current tax rises, and the deferred tax liability unwinds. Over the full life of the asset, total tax paid is the same either way. Deferred tax accounting simply prevents the reported income tax expense from looking like a roller coaster.

The same reconciliation runs in reverse with warranty costs. A company accrues a $2 million warranty reserve on its books this year but gets no tax deduction until repairs are performed. Current tax is higher than book income would suggest, and a deferred tax asset sits on the balance sheet representing the future benefit. When the repairs happen and the deduction lands, the deferred tax asset shrinks and the current tax bill drops. Total tax over time stays the same. Deferred tax accounting smooths the reported expense across periods so it tracks with the economics of the underlying business.

Reading the Numbers on the Financial Statements

On the income statement, total tax expense splits into two lines: the current portion (what the company actually owes this year) and the deferred portion (the change in deferred tax balances during the year). A year with large equipment purchases might show a small current tax expense alongside a significant increase in the deferred tax liability, so total tax expense stays roughly proportional to book income even though the cash outflow is much smaller.

On the balance sheet, all deferred tax assets and liabilities are classified as noncurrent, regardless of when the underlying temporary difference is expected to reverse.11FASB. ASU 2015-17 – Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes Within a single tax jurisdiction, deferred tax assets and liabilities are netted against each other and shown as a single noncurrent amount.

The Effective Tax Rate Reconciliation

Financial statement footnotes include a reconciliation walking from the 21 percent statutory federal rate to the company’s actual effective rate. That table breaks out the impact of state taxes, permanent differences like nondeductible fines or tax-exempt interest, foreign rate differentials, tax credits, and changes in the valuation allowance. Public companies face enhanced disclosure requirements for annual periods beginning after December 15, 2024, requiring more granular breakdowns of reconciling items that exceed a quantitative threshold.

A company whose effective rate consistently runs several points below the statutory rate because of R&D credits and foreign structures is in a different position from one whose rate looks low only because it released a large valuation allowance. The first is durable tax planning. The second is a one-time accounting event. Current and deferred tax, read together with the rate reconciliation, are what separate the two.