Subpart F Income and Controlled Foreign Corporations — Anti-Deferral Rules

Before 1962, a U.S. taxpayer could often defer U.S. tax on foreign-subsidiary earnings until an actual distribution. Subpart F changed that. Enacted in 1962 and now codified principally in 26 U.S.C. §§ 951-965, the Subpart F rules require certain U.S. shareholders of a controlled foreign corporation (CFC) to include specified categories of CFC income in current U.S. taxable income even if the CFC makes no dividend distribution. Subpart F is still the core anti-deferral regime for insurance income, foreign base company income, and other specifically targeted categories. The post-2017 GILTI regime broadened current inclusion for CFC earnings, but Subpart F remains independently important because it determines category, timing, foreign-tax-credit treatment, and previously taxed earnings and profits (PTEP/PTI) consequences.

Current Law (2026)

Parameter	Value
Core statutes	26 U.S.C. §§ 951–965
CFC definition	Foreign corporation in which U.S. shareholders (≥10% each) collectively own more than 50% of vote or value (§ 957)
U.S. shareholder threshold	≥10% of voting power or value (post-TCJA 2017)
Subpart F income categories	Insurance income (§ 953); foreign base company income and certain other specifically listed categories under § 952 / § 954
Foreign personal holding company income	Dividends, interest, rents, royalties, annuities — unless from an active business
Foreign base company sales income	Income from buying from or selling to related parties when the CFC isn't where the goods are manufactured or sold
Foreign base company services income	Income from services performed for related parties outside the CFC's country
De minimis rule	If Subpart F income is less than 5% (or $1M) of total gross income, none is Subpart F
Full inclusion rule	If Subpart F income is more than 70% of total gross income, all gross income is Subpart F
High-tax exception	By election, certain Subpart F income subject to an effective foreign tax rate above 90% of the U.S. corporate rate (18.9% under current 21% corporate rate) may be excluded
GILTI interaction	GILTI covers the non-Subpart F income of CFCs under § 951A; Subpart F and GILTI cannot both apply to the same income
§ 965 transition tax	One-time inclusion of pre-2018 accumulated CFC E&P at 8% / 15.5% rates; mostly historical now, but still relevant where taxpayers elected installment payments or must track related PTI attributes

Legal Authority

26 U.S.C. § 951 — Inclusions in gross income: U.S. shareholders of CFCs must include their pro rata share of the CFC's Subpart F income in their own income annually; also requires inclusion of the GILTI amount under § 951A; the inclusion happens whether or not the CFC distributes any cash
26 U.S.C. § 952 — Subpart F income defined: includes (1) insurance income and (2) foreign base company income; also includes income from countries under international boycott, income from countries supporting terrorism, and income from illegal bribes/kickbacks
26 U.S.C. § 953 — Insurance income: premiums received from insuring risks outside the CFC's home country are Subpart F income — designed to prevent captive insurance structures from sheltering income offshore
26 U.S.C. § 954 — Foreign base company income: the core Subpart F category; includes foreign personal holding company income (passive income), foreign base company sales income (back-to-back transactions between related parties using the CFC as an intermediary), and foreign base company services income (services for related parties performed outside the CFC's country of incorporation)
26 U.S.C. § 957 — CFC defined: any foreign corporation in which U.S. shareholders (each owning ≥10%) collectively own more than 50% of the total combined voting power or total value; TCJA 2017 expanded the definition by eliminating the requirement that U.S. shareholders each own 10% by vote — 10% by value now also counts
26 U.S.C. § 959 — Exclusion from gross income of previously taxed earnings (PTI): when a CFC distributes earnings that were previously included in a U.S. shareholder's income under Subpart F, those earnings are excluded from income again — preventing double taxation of the same earnings
26 U.S.C. § 960 — Deemed paid foreign tax credit: U.S. corporations that include Subpart F income are entitled to a deemed paid foreign tax credit for the foreign taxes attributable to that income, reducing (but not always eliminating) U.S. tax on the inclusion
26 U.S.C. § 965 — Transition tax: for the last taxable year beginning before January 1, 2018, U.S. shareholders included their pro rata share of the CFC's post-1986 accumulated E&P not yet repatriated at a blended rate (15.5% for cash and cash equivalents; 8% for other assets); taxpayers who elected the 8-year installment schedule are still making payments in 2026

How It Works

Subpart F is a current-inclusion regime — tax is owed by the U.S. shareholder on the CFC's specified earnings in the year the CFC earns them, without waiting for a distribution. This distinction is fundamental: the U.S. shareholder owes U.S. tax on passive income, foreign base company sales income, and other Subpart F categories even if the foreign subsidiary retains every dollar and pays no dividend. Two sequential determinations govern who is affected: first, whether the foreign entity is a CFC under § 957 (a foreign corporation where U.S. shareholders own more than 50% by vote or value); second, which U.S. persons qualify as U.S. shareholders under § 951(b) (any U.S. person who owns 10% or more of the CFC by vote or value). Only U.S. shareholders of a CFC are subject to Subpart F inclusions — holding less than 10% means no inclusion regardless of the CFC's income. A high-tax exception is available when the CFC's income was taxed by the foreign country at a rate exceeding 90% of the U.S. rate, but the exception is elective and technical — it requires affirmative annual election and correct application of the regulatory grouping rules; it does not automatically remove high-taxed income from Subpart F. Subpart F inclusions and GILTI (Global Intangible Low-Taxed Income) are coordinated so the same income isn't taxed twice: income already included under Subpart F is excluded from the GILTI tested-income calculation. Once income is included under Subpart F, it becomes Previously Taxed Income (PTI/PTEP) — tracking these accounts is essential for avoiding double taxation when the CFC later distributes earnings and for computing foreign tax credit consequences. The annual compliance vehicle is Form 5471, where all of this work surfaces through category-specific schedules, E&P calculations, PTEP accounts, and foreign-tax reporting. The detailed mechanics for each income category — FBCSI, passive income, the high-tax exception, and GILTI coordination — are in the section below.

How Subpart F Works

Subpart F operates as an anti-deferral mechanism. Here's the key concept: normally, a U.S. corporation pays U.S. tax on dividends from a foreign subsidiary only when the subsidiary distributes them. Subpart F accelerates the inclusion — the U.S. shareholder must include specified income categories now, in the year earned, as if they had received a constructive dividend.

A U.S. shareholder is any U.S. person (individual, corporation, partnership, trust, estate) that owns at least 10% of the CFC's voting power or value. Post-TCJA, the constructive ownership rules under § 958(b) were expanded so that downward attribution can make a U.S. person a "U.S. shareholder" even without any direct ownership — creating traps for joint ventures where a foreign partner constructively owns the U.S. shareholder's CFC shares.

What is Subpart F income? The most common categories in practice:

Foreign personal holding company income (FPHCI): Dividends, interest, rents, royalties, and annuities received by the CFC. Exception: rents and royalties from active conduct of a trade or business are not FPHCI. Also excepted: interest earned by banking institutions from banking operations, dividends between related CFCs, and certain income from active leasing and lending.

Foreign base company sales income (FBCSI): Income from buying personal property from (or on behalf of) a related person and selling it to (or on behalf of) a related person, where the property is manufactured outside the CFC's country and sold for use outside the CFC's country. Classic example: a Swiss trading company that buys goods from a U.S. parent, sells them to Asian customers, and earns the profit — if both the manufacturer and the customers are related to the Swiss company, that income is FBCSI. The prices the parent and the Swiss company charge each other must also satisfy the § 482 transfer pricing arm's-length standard, which is separately enforced.

Foreign base company services income: Services performed for related parties, for use outside the CFC's country of incorporation. A Bermuda service entity that provides technical support to a U.S. parent's customers worldwide earns Subpart F income on those fees.

Previously Taxed Earnings (PTI): The Offset When Cash Arrives

When a CFC eventually distributes earnings that were already included in income under Subpart F, § 959 excludes those distributions from income to avoid double taxation. The U.S. shareholder has a "previously taxed income" account tracking what has already been included. Distributions come first out of PTI (tax-free), then out of E&P not previously taxed (taxable as a dividend).

Tracking PTI is critical in practice — and complex when CFCs change ownership, when there are multiple layers of CFCs, or when GILTI and Subpart F inclusions mix.

Subpart F vs. GILTI

The TCJA's Global Intangible Low-Taxed Income (GILTI) regime under § 951A expanded anti-deferral to cover essentially all CFC income. GILTI sweeps in the income that Subpart F doesn't cover — but GILTI and Subpart F are not duplicative. Subpart F income is excluded from the GILTI calculation. The practical consequence: Subpart F income (passive income, sales income, services income) is generally treated more harshly than GILTI — Subpart F doesn't have the GILTI high-tax exclusion as built-in (though one now exists by regulation) and doesn't benefit from the § 250 deduction available to GILTI inclusions. A parallel anti-avoidance tool, the base erosion and anti-abuse tax (BEAT), targets deductible payments to foreign affiliates that sit outside both Subpart F and GILTI.

How It Affects You

If you're a U.S. shareholder in a foreign subsidiary: The threshold for Subpart F obligations is lower than most founders and investors expect. You are a "U.S. shareholder" if you own 10% or more of a foreign corporation's voting power or value — and if U.S. shareholders collectively exceed 50% ownership, the entity is a CFC and every 10%+ U.S. owner is subject to annual Subpart F inclusions. The key filing is Form 5471 — an IRS form that requires detailed reporting of the CFC's income, assets, liabilities, and transactions with related parties. Failure to file Form 5471 triggers a $10,000 penalty per form per year, and the statute of limitations on the entire tax return remains open until the form is filed. Holders of smaller minority stakes in foreign funds may instead fall under the PFIC passive foreign investment company regime, and individual U.S. persons generally also face FATCA foreign account reporting. Start compliance the first year you hit the 10% threshold, not when the CFC becomes profitable.

If your foreign subsidiary earns passive or related-party income: The specific income categories matter enormously. A CFC that earns dividends, interest, rents, or royalties from passive investments — "foreign personal holding company income" — faces immediate Subpart F inclusion at the U.S. shareholder level, taxed at ordinary income rates (not capital gains rates). A CFC that buys goods from a related U.S. parent and sells them to customers in a third country — without manufacturing in its own country — earns "foreign base company sales income," also Subpart F. The practical test: if the foreign subsidiary is a shell or conduit earning income divorced from its location, Subpart F captures it. A de minimis exception applies if Subpart F income is less than 5% of total gross income (or $1 million) — below that floor, none of the income is Subpart F. But if Subpart F income exceeds 70% of total gross income, all gross income becomes Subpart F.

If you're a private equity investor or LP in a fund with foreign portfolio companies: TCJA's 2017 downward attribution rule change dramatically expanded CFC exposure for fund investors. Before TCJA, foreign-to-foreign attribution didn't flow to U.S. persons; after TCJA, a U.S. limited partner in a foreign fund can be deemed a 10% U.S. shareholder in a CFC that the fund owns — triggering Subpart F and GILTI inclusions — even if the LP's direct interest in the fund is small. Fund sponsors should analyze whether the LP structure creates U.S. shareholder status and, if so, whether the fund's income flows are Subpart F or GILTI — the two regimes cannot both apply to the same income, but the categorization affects whether the §954(b)(4) high-tax exception or the GILTI high-tax exclusion applies.

If you have a 50/50 joint venture with a foreign partner: The CFC definition requires U.S. shareholders to collectively own more than 50% — not exactly 50%. If a U.S. company and a single foreign partner each own 50%, the entity may not technically be a CFC. But constructive ownership rules under §318 and §958 can attribute shares owned by related parties, turning a nominal 50/50 into a deemed majority U.S. ownership. Any joint venture in the 40–60% U.S. ownership range deserves careful analysis of the attribution rules before assuming no Subpart F obligations.

State Variations

Most states did not conform to the TCJA's federal Subpart F changes immediately. California, New York, and many other states have their own treatment for CFC income — some states follow federal Subpart F inclusions while others require separate calculations. State Subpart F conformity analysis is a significant compliance issue for multinationals.

Implementing Regulations

26 CFR 1.951-1 through 1.951-3 — Core Subpart F inclusion rules, including the current-year inclusion mechanics and certain shareholder computations
26 CFR 1.952-1 through 1.952-2 — Definition and treatment of Subpart F income
26 CFR 1.954-1 through 1.954-2 — Foreign base company income rules, including the high-tax exception election framework and category definitions
26 CFR 1.957-1 — Controlled foreign corporation definition rules
26 CFR 1.959-1 through 1.959-3 — Previously taxed earnings and profits exclusion and ordering rules
26 CFR 1.960-1 through 1.960-3 — Deemed-paid foreign tax credit rules for Subpart F and related inclusions
26 CFR 1.965-1 through 1.965-8 — Transition-tax rules, including installment-payment elections and related mechanics

Pending Legislation (119th Congress)

As of April 8, 2026, no enacted federal law has displaced the core Subpart F and CFC framework summarized here. Congress, Treasury, and practitioners continue to debate the relationship among Subpart F, GILTI, Pillar Two, and broader international-tax reform, but this page should be read based on the current §§ 951-965 regime unless Congress enacts a change.

Recent Developments

2021-2022 final regulations remain the core modern framework: Treasury and the IRS finalized major regulations on high-tax elections, PTI ordering, and the interaction among Subpart F, GILTI, and foreign-tax-credit rules, and those rules continue to shape 2026 compliance.
2025 Form 5471 instructions: Current IRS instructions continue to emphasize category-by-category PTI, foreign-tax, and Subpart F reporting, showing that the operational complexity of these rules remains very much alive even when the core statute is old.
2025-2026 IRS guidance reflects ongoing PTI / foreign-tax administration: Recent Form 5471 instructions and related notices continue to address how taxes related to previously taxed earnings and profits are reported and allocated.
Section 965 is now mostly a tail issue: For taxpayers that elected the § 965(h) installment schedule, the later installments are still relevant in 2026, but for most taxpayers the transition tax is now a compliance-and-accounting legacy issue rather than the main current-law story.