The high-tax exception under IRC Section 954(b)(4) lets U.S. shareholders of a controlled foreign corporation exclude an item of Subpart F income from current U.S. taxation when that item already bears a foreign effective tax rate above 18.9%. The exclusion is not automatic. The controlling U.S. shareholders must affirmatively elect it, the calculation must be run separately for each tested unit and each Subpart F category, and the choice carries downstream effects on GILTI, foreign tax credits, and how future distributions are taxed.
The 18.9% Threshold and What Income Qualifies
The U.S. corporate rate is a flat 21%, and 90% of that is 18.9%. That figure is the bright line. If an item of income bears a foreign effective tax rate at or above 18.9%, it can qualify for exclusion; miss it by any margin and the exception is unavailable for that item.1Office of the Law Revision Counsel. 26 U.S. Code 954 – Foreign Base Company Income
Only certain income categories are eligible: foreign personal holding company income, foreign base company sales income, foreign base company services income, and gross insurance income.2National Archives. Guidance Under Section 954(b)(4) Regarding Income Subject to a High Rate of Foreign Tax Income already excluded from Subpart F on other grounds cannot use this exception, and income outside these categories is not eligible at all.
How to Calculate the Effective Tax Rate
The effective tax rate calculation is the mechanical core of the exception. Small errors in either the numerator or denominator can pull the result below 18.9% and disqualify an item that looked like it should have cleared.
Grouping by Tested Unit and Income Category
You cannot cherry-pick a single high-taxed stream to clear the threshold while ignoring lower-taxed income in the same category. Income has to be grouped by tested unit, and within each tested unit by Subpart F category, before the effective rate is run.3eCFR. 26 CFR 1.951A-2 – Tested Income and Tested Loss
A tested unit is generally the CFC itself, but it can also be a branch or an interest in a pass-through entity that is treated as having a separate taxable presence in a foreign country. Tested units that are tax residents of, or have a taxable presence in, the same foreign country are generally combined. A branch that does not create a taxable presence where it operates is not combined with tested units in that country.
Within each tested unit, items go into their Subpart F buckets: foreign personal holding company income in one, foreign base company sales income in another, and so on. The rate is calculated separately for each bucket within each unit. That structure keeps a high tax on one type of income from subsidizing a low tax on another.
The Denominator
The denominator starts with the CFC’s income for the group, recomputed under U.S. tax principles rather than the foreign country’s books. That means U.S. depreciation methods, U.S. inventory rules, and U.S. expense capitalization, as if the CFC were computing earnings and profits domestically.
Payments between tested units of the same CFC that the foreign country disregards still have to be accounted for when working out each unit’s net income. Related-party expenses and income between units are eliminated or reallocated so each denominator reflects actual economic activity. General and administrative expenses and interest expense must be allocated and apportioned to each income group.
Getting the denominator wrong is the most common way the calculation fails. An artificially low denominator inflates the rate and can make income look like it qualifies when it does not.
The Numerator
Only foreign income taxes qualify. Value-added taxes, property taxes, excise taxes, and other levies that are not creditable income taxes under U.S. law do not count. If a foreign tax is partially refundable or subject to a rebate, the numerator uses the net amount.
The foreign taxes must also be specifically allocated to the income group that forms the denominator. A lump-sum foreign tax liability across all of the CFC’s operations has to be broken down and attributed to the right tested unit and the right category. That allocation generally follows foreign law but is adjusted where U.S. sourcing rules produce a different result.
The formula divides foreign income taxes paid or accrued by the sum of the tentative net income plus those same foreign taxes. That gross-up in the denominator is easy to overlook and changes the math against you compared to a simple taxes-over-net-income ratio.
A Worked Example
A CFC earns $1,000,000 of foreign personal holding company income in Country X and pays $220,000 of foreign income tax on that income. After recomputing under U.S. principles, tentative net income comes to $980,000. Under the gross-up formula, the rate is $220,000 ÷ ($980,000 + $220,000) = 18.33%. That falls below 18.9%, so the item does not qualify despite a foreign tax rate that looked substantial. Had the tax been $233,000, the rate would be $233,000 ÷ $1,213,000 = 19.21%, clearing the line.
Making the Election
Even when every eligible item clears 18.9%, none of it is excluded unless the U.S. shareholder actually elects the exception.
Who Elects and How
The election is made by the “controlling United States shareholders” of the CFC as defined under Section 1.964-1(c)(5). It is made by attaching a statement to the controlling shareholder’s original or amended income tax return for the CFC’s taxable year, identifying the CFC and the year. Once made, the election binds all U.S. shareholders of that CFC for the year.4GovInfo. 26 CFR 1.954-1 – Foreign Base Company Income
Consistency Across Items and CFCs
Under the existing regulations, if the election is made, all items of passive foreign personal holding company income eligible for the exception must be excluded as a group. You cannot selectively exclude some qualifying passive items while keeping others in Subpart F.
Proposed regulations issued in 2020 would go further, replacing the CFC-by-CFC election with a single unified election that would apply to every CFC in a CFC group, covering both Subpart F and GILTI at once.2National Archives. Guidance Under Section 954(b)(4) Regarding Income Subject to a High Rate of Foreign Tax If those regulations are finalized, a shareholder with multiple CFCs will no longer be able to elect for one and decline for another in the same group. Modeling the exception across the whole structure becomes necessary before electing for any single entity.
Revocation and Late-Election Relief
The election generally binds the year it covers. For a later year, the controlling shareholders can simply decline to elect again without IRS permission. Undoing an election for the same year it was made requires IRS consent, which effectively prevents retroactive optimization after the year’s numbers are in.
A missed election is not necessarily permanent. Regulations under Sections 301.9100-1 through 301.9100-3 provide a framework for late-election relief, including an automatic 12-month extension for some regulatory elections and, failing that, discretionary relief through a private letter ruling with a user fee. In many cases the ruling path is the more realistic route. Relief is not guaranteed, and the cost and delay of pursuing it are reasons to get the election right on the original return.
What the Election Changes
Subpart F and GILTI
The direct effect is that qualifying income drops out of Subpart F, so U.S. shareholders do not include it in current-year gross income. The income stays in the CFC’s earnings and profits but is not treated as previously taxed income; it sits in the general E&P pool until something triggers U.S. taxation.
Income excluded by the high-tax exception is also excluded from tested income under GILTI. Section 951A(c)(2)(A)(i)(III) specifically carves out income excluded by reason of Section 954(b)(4).5Office of the Law Revision Counsel. 26 U.S. Code 951A – Net CFC Tested Income Included in Gross Income of United States Shareholders Without that carve-out, income that escaped Subpart F could still get swept into the GILTI base. The exception is effectively a single gate that keeps highly taxed income out of both regimes.
For 2026, corporate U.S. shareholders can deduct 50% of their GILTI inclusion under Section 250, producing an effective U.S. rate of 10.5% on GILTI before foreign tax credits.6Office of the Law Revision Counsel. 26 U.S. Code 250 – Foreign-Derived Deduction Eligible Income and Global Intangible Low-Taxed Income With the 50% deduction in place and the 80% foreign tax credit limitation under GILTI, foreign taxes at roughly 13.125% or above can fully offset the GILTI tax. Because the exception’s 18.9% threshold sits well above that break-even point, the exception is most valuable for income that would otherwise generate excess foreign tax credits the shareholder cannot use currently under GILTI’s limits.
Distributions of Excluded Earnings
Because excluded income is not previously taxed income, any eventual distribution of those earnings is a taxable dividend. For corporate shareholders, Section 245A provides a 100% dividends-received deduction for the foreign-source portion of dividends from a CFC, which can eliminate U.S. tax on the distribution if the ownership and holding-period requirements are met.7Office of the Law Revision Counsel. 26 U.S. Code 245A – Deduction for Foreign Source-Portion of Dividends Individual shareholders have no comparable deduction, so the dividend is taxable at the applicable rate, with foreign tax credits associated with the distributed earnings becoming available at that point.
Foreign Tax Credit Timing
Foreign taxes paid on excluded income are not available to offset U.S. tax in the year the income is earned, because the underlying income has been removed from the U.S. tax base. Those taxes stay with the CFC’s E&P and become available as deemed-paid credits under Section 960 when the earnings are eventually distributed or otherwise included.8Office of the Law Revision Counsel. 26 U.S. Code 960 – Deemed Paid Credit for Subpart F Inclusions The exception thus defers both the income inclusion and the related credit into the same future period.
That deferral matters most when a shareholder has other foreign-source income generating excess credit capacity. Losing the current-year credit on high-taxed income means fewer credits available to cross-credit against lower-taxed foreign income. The election decision should account for the shareholder’s overall credit position, not just the CFC in isolation.
When Electing Makes Strategic Sense
Electing the exception trades a current Subpart F inclusion with current credits for deferred taxation on a future distribution with deferred credits. That trade favors the election in some situations and hurts in others.
The election tends to pay off when the CFC operates in a jurisdiction with a corporate rate near or above 18.9%, the shareholder has no immediate use for excess foreign tax credits, and the earnings are unlikely to be repatriated soon. Corporate shareholders benefit most because Section 245A can eliminate U.S. tax on eventual distributions, making the deferral effectively permanent. For individual shareholders without a dividends-received deduction, the calculus is less favorable because the deferred income will eventually be taxed as a dividend.
The election becomes risky when the credit position is tight. Removing high-taxed income and its associated credits from the current year shrinks the pool available to offset U.S. tax on other foreign-source income. If the shareholder has lower-taxed CFC income that would benefit from cross-crediting, keeping the high-taxed income in Subpart F and using the credits currently may produce a better after-tax result overall.
Groups with multiple CFCs face additional complexity under the proposed unified election framework. If those regulations are finalized, one CFC with a borderline rate or unfavorable credit position can force a group-wide decision that would not have been necessary under the older CFC-by-CFC approach.
Compliance and Penalty Exposure
U.S. shareholders of CFCs already file Form 5471, and the election and its supporting calculations must be documented and attached to the return. Failing to file a complete and correct Form 5471 triggers a $10,000 penalty per form. If the IRS sends a notice of failure and the form is not filed within 90 days, an additional $10,000 accrues for each 30-day period, up to a maximum of $50,000 per form.9Internal Revenue Service. International Information Reporting Penalties
The rate calculation requires tracing foreign taxes and recomputing income under U.S. principles for each tested unit and category. Records supporting the E&P adjustments, expense allocations, tax computations, and tested unit groupings should be retained at least as long as the statute of limitations remains open, generally three years from filing, extending to six years if unreported income exceeds 25% of gross income shown.10Internal Revenue Service. How Long Should I Keep Records? For structures that may generate gain or loss on disposition, indefinite retention is safer.
An incorrect election that understates U.S. tax can also trigger a 20% accuracy-related penalty on the underpayment. The penalty applies where the understatement results from negligence or disregard of regulations, or where it qualifies as a substantial understatement, which for corporations other than S corporations means the understatement exceeds the lesser of 10% of the tax required to be shown (or $10,000, whichever is greater) or $10,000,000.11Office of the Law Revision Counsel. 26 U.S. Code 6662 – Imposition of Accuracy-Related Penalty on Underpayments Because the rate calculation involves multiple judgment calls on expense allocation and E&P adjustments, contemporaneous documentation of each step is the most reliable defense.