Subpart F & GILTI: When Your Foreign Sub Triggers US Tax Before Any Distribution

A Bay Area founder who owns 60% of a UK Ltd with $400K of net income can pay $130,000 of US and California tax on income they never received as cash, before any Form 5471 penalty (which starts at $10,000 per missed year). If you set up a Cayman holdco in San Jose for your fund-friendly cap table, opened an Indian Pvt Ltd to hire engineers, registered an Estonian e-residency company for your SaaS billing, or rolled a UK Ltd to handle European customers, you probably did it for a clean operational reason. Then the first US tax season after incorporation hits, your CPA asks about ownership percentages and entity classification, and the numbers start moving in directions you did not expect. Income you never took as a distribution shows up on your personal 1040 anyway, taxed at your top marginal rate.

That is the Subpart F and GILTI regime. US tax law has two anti-deferral systems that exist specifically to prevent US persons from parking earnings in offshore corporations and waiting forever to pay tax. If you own 10% or more of a controlled foreign corporation, both regimes can attribute the company's income to you in the current year, with no cash in your pocket to cover the bill.

The good news is that the worst-case outcome is almost always avoidable with structure choices made in advance. The bad news is that almost no founder learns about these rules before the first Form 5471 is overdue. This guide walks the mechanics, the math, and the planning levers, and it is one of the most common conversations we have with founders we work with at Silicon Valley Tax.

Why This Matters: The Bay Area Founder Pattern

A pattern we see constantly. A founder incorporates Delaware C-corp for the US business, then spins up a foreign subsidiary for one of these reasons:

• An Indian or Eastern European Pvt Ltd to employ a remote dev team locally without running a US payroll across borders
• A UK Ltd or Irish Designated Activity Company to bill European customers in EUR and handle VAT
• A Cayman or BVI holdco to hold IP or to satisfy a fund's cap table preference
• An Estonian or Singaporean entity opened on e-residency for fintech or marketplace reasons
• An Israeli Ltd because the technical co-founder or acquired team is based there

None of these are exotic. All of them, the moment a US person owns enough of the foreign company, drag the US shareholders into the Subpart F and GILTI regimes. The default assumption that "the foreign company pays foreign tax and that is that" is wrong for US owners. The US has been clawing back deferred offshore earnings since 1962 (Subpart F) and aggressively since 2018 (GILTI).

Step 1: Is It a Controlled Foreign Corporation?

The whole regime turns on whether the foreign company is a Controlled Foreign Corporation, or CFC, under IRC Section 957. The test has two parts:

1. Count the US shareholders. A "US shareholder" for these purposes is any US person who owns 10% or more of the foreign corporation by vote or by value, applying constructive ownership rules from IRC Section 958. The 10% threshold is per-person, not per-family.
2. Aggregate their ownership. If those 10%-or-more US shareholders together own more than 50% of the foreign corp's vote or value, the company is a CFC.

Almost every founder-controlled foreign sub is a CFC. If you incorporated a UK Ltd and own 100% of it, you are a CFC. If you and a US co-founder each own 30% of a Cayman holdco, you are both 10%-plus shareholders and together own more than 50%, so it is a CFC. If you own 40% and a French citizen owns 60%, the French shareholder does not count toward the US shareholder pool, you are the only US shareholder, you own less than 50%, and it is not a CFC. The arithmetic matters.

Once a foreign corp is a CFC, every US shareholder (10% or more) gets dragged into both Subpart F and GILTI for their pro-rata share of the company's income, regardless of distribution.

Step 2: Subpart F (The Original Anti-Deferral Regime)

Subpart F, codified at IRC Section 951, dates to 1962 and was Congress's first answer to offshore deferral. It targets "tainted" income, mostly passive and related-party stuff that the US considers ripe for tax abuse:

• Foreign personal holding company income: interest, dividends, rents, royalties, capital gains
• Foreign base company sales income: goods bought from or sold to a related party where the goods are neither produced nor consumed in the CFC's country
• Foreign base company services income: services performed outside the CFC's country for or on behalf of a related party
• Insurance income from insuring non-CFC-country risks

If your CFC earns this income, your pro-rata share flows through to your personal 1040 as ordinary income in the current year, taxed at your top marginal rate. No distribution required. No deferral available.

There is a useful high-tax exception: if the foreign country taxes the income at more than 90% of the US corporate rate (so above 18.9% currently), you can elect out of Subpart F for that income. Per the 2020 final regulations under Treas. Reg. §1.954-1(d), the election is made item-by-item within categories, not entity-wide. That is why UK-source royalties or Irish operating profits often escape Subpart F. Cayman-source anything (0% tax) almost always gets caught.

For active operating businesses (you sell SaaS to your own customers, you build product in-country, you provide services in your CFC's country), Subpart F usually does not bite hard. It is GILTI that hits operating businesses.

Step 3: GILTI (The Bigger Problem for Most Founders)

The Tax Cuts and Jobs Act of 2017 added IRC Section 951A, the Global Intangible Low-Taxed Income regime. GILTI was supposed to capture earnings that Subpart F missed, particularly active business income from asset-light foreign subs (think IP holdcos, software dev shops, services companies with little PP&E). In practice GILTI applies to almost every CFC with meaningful earnings.

Here is how the calculation works for each US shareholder of a CFC:

1. Start with the CFC's "tested income" (basically net income, with some adjustments and excluding Subpart F income already taxed)
2. Subtract a "deemed return on tangible assets" equal to 10% of the CFC's qualified business asset investment (QBAI, the depreciable tangible property basis)
3. The remainder is GILTI, included on the US shareholder's personal 1040 as ordinary income in the current year

The structural problem: a software company has almost no tangible assets. QBAI is near zero. So the "deemed return" subtraction is near zero. Almost 100% of the CFC's earnings get pulled into GILTI.

For an individual US shareholder filing personally, GILTI hits at your top marginal rate (37% federal in 2026), plus state tax, plus potentially the 3.8% Net Investment Income Tax (subject to IRS guidance on NII treatment of GILTI inclusions for non-active individuals). California adds up to 13.3%. The all-in cost on GILTI for a high-income San Jose founder is in the 50%+ range. On income you did not receive as cash.

Step 4: The Section 962 Election (Your Main Defense)

This is the single most important planning move for an individual CFC owner. IRC Section 962 lets an individual US shareholder elect, year by year, to be taxed on Subpart F and GILTI inclusions as if they were a domestic C corporation. That election unlocks two things that are otherwise unavailable to individuals:

1. The 50% Section 250 deduction on GILTI, under IRC Section 250 (which only applies to corporate taxpayers by default). Note: the 50% rate is scheduled to drop to 37.5% for tax years after 12/31/2025 under current law; this rate is subject to legislative status and should be verified before relying on the 50% figure.
2. A foreign tax credit for the foreign corporate tax the CFC paid, at the corporate rate

The math: GILTI inclusion, taxed at 21% corporate rate, with the 50% Section 250 deduction (or 37.5% if the rate has stepped down per current statute), gives an effective US rate of roughly 10.5% (or 13.125% post-step-down) before foreign tax credit. The foreign tax credit then offsets up to 80% of the deemed-paid foreign corporate tax. For a CFC sitting in a moderate-tax jurisdiction (UK, Germany, Japan, Australia, Canada), the FTC usually wipes out the residual US tax on GILTI entirely.

The catch with Section 962: when the CFC eventually distributes the previously-taxed earnings to you, the distribution is taxed again at qualified-dividend rates (to the extent the distribution exceeds the US tax you already paid). So Section 962 trades current ordinary-income treatment for a future second layer of tax at lower rates. For founders who plan to reinvest in the foreign business rather than repatriate quickly, that is a great trade. For founders who plan to pull the cash out in 18 months, the math is less clear.

Step 5: Form 5471 (And the Penalties That Catch Everyone)

Whether or not you owe Subpart F or GILTI tax in a given year, if you are a US person who is a 10%-or-more shareholder, officer, or director of a foreign corp, you almost certainly owe an annual Form 5471 attached to your 1040 (or to the parent C-corp's 1120). The form is dense, multi-schedule, and the IRS treats it as informational reporting with hard penalties.

The penalty structure: $10,000 per missed Form 5471, per year, per CFC, plus an additional $10,000 for every 30 days the form remains unfiled after IRS notice (capped at $50,000 per form). The IRS has been auto-assessing these penalties since 2018 under a programmatic notice system. Reasonable-cause relief is available but increasingly difficult to obtain.

If you have owned a foreign company for three years and never filed Form 5471, your exposure is $30,000 minimum, possibly more if multiple shareholders have the same gap. We have walked clients through delinquent-filing procedures and streamlined disclosure programs many times. The cheapest path is to file on time. The second-cheapest is to come in voluntarily under the right program before the IRS finds you.

Worked Example: UK Dev Sub, With and Without Section 962

Take a representative case. You own 60% of a UK Ltd that runs your engineering team. The UK Ltd has $400,000 of net income for the year. QBAI is negligible (a few laptops, no real estate). The UK pays 25% corporate tax, leaving $300,000 of after-tax income. The UK Ltd retains all of it for hiring and operations. You take zero distribution. You live in San Jose, top federal and California brackets, subject to NIIT.

Your GILTI inclusion: 60% of $400,000 = $240,000 of tested income, minus near-zero QBAI deduction, so roughly $240,000 of GILTI.

Without Section 962 (default individual treatment)

• Federal tax at 37%: $88,800
• California tax at 13.3%: $31,920
• NIIT at 3.8%: $9,120
• Total US tax on GILTI: roughly $129,840
• No foreign tax credit for the UK corporate tax (FTC for individuals on GILTI is severely limited without the 962 election)
• You owe $129,840 to US/CA on $0 of cash received

With Section 962 election

• Treated as corporate taxpayer for the GILTI inclusion
• 21% corporate rate on $240,000 = $50,400 pre-deduction
• 50% Section 250 deduction reduces taxable GILTI to $120,000, US tax = $25,200
• Deemed-paid foreign tax credit: 80% of (60% of UK's $100,000 corporate tax) = $48,000 FTC available
• FTC fully absorbs the $25,200 of residual US tax. Net federal tax: $0
• California: California does not conform to Section 962 cleanly. California taxes GILTI as ordinary income to the individual without the federal benefits. Cost: roughly $31,920
• NIIT: still applies to the inclusion, roughly $9,120
• Total US tax with 962: roughly $41,040

The Section 962 election saves this founder roughly $88,800 per year. Over a three-year period before the founder repatriates earnings, that is a quarter-million dollars in deferred tax. Even after the eventual qualified-dividend tax on distribution, the net savings is typically six figures for this kind of profile.

Note the California issue. California is a recurring drag on international tax planning, just like it is on QSBS. Founders considering this structure should understand the state cost up front, not at filing time.

What Goes Wrong Without a CPA

The most common Subpart F / GILTI mistake we see at intake: a Bay Area founder owns a UK Ltd or Indian Pvt Ltd for two-to-three years, never files Form 5471 (no one told them about it at incorporation), and walks in with $20,000-$50,000 in stacked §6038 penalties plus a missed §962 election that converts what should have been $0 of residual US tax into $130,000-$260,000 of personal liability per CFC. Founders who try to handle this in TurboTax routinely miss the CFC analysis itself (constructive ownership under §958 is non-obvious), the check-the-box election window on Form 8832 that would have eliminated the CFC regime entirely, and the high-tax election under the 2020 final regs. DIY tax software does not even prompt for Form 5471. Those are the items where engagement pays for itself many times over.

Planning Levers Beyond Section 962

Section 962 is the most common move, but it is not the only one. Depending on facts, the right call may be structural rather than elective.

• Check-the-box election on Form 8832. For many foreign entity types (UK Ltd, Singapore Pte Ltd, Cayman exempted company, and many others on the IRS "per se" list exceptions), you can file Form 8832 to elect to treat the foreign company as a disregarded entity (if single owner) or partnership (if multiple owners) for US tax purposes. The CFC regime disappears because there is no foreign corporation in the US tax view. Foreign tax credits flow through directly. The trade-off: you lose deferral entirely, all foreign earnings flow to your personal 1040 in the current year regardless of CFC status. For an operating business with full foreign tax payment, check-the-box plus FTC often beats the CFC-plus-962 path.
• Hold the foreign sub under a US C-corp. If the foreign sub is owned by your US C-corp instead of by you personally, GILTI still applies but at the corporate level where the 50% Section 250 deduction and corporate FTC are available by default (no Section 962 election needed). For founders who already operate through a US C-corp, holding international subs under the C-corp rather than personally is usually the cleaner default.
• Stay below the 10% threshold if you can. Easier for early-stage angel investors than for founders, but if you can structure investment so no single US person crosses 10%, no CFC US shareholder exists, and the foreign company is not a CFC. Constructive ownership rules can defeat this if not designed carefully.
• Section 965 transition tax (one-time event from 2017 reform) still occasionally comes up for owners of pre-2018 foreign subs with accumulated untaxed earnings. See IRC Section 965 and the late-filing implications if you have an older foreign sub that was never properly reported.

Action Items

• If you own any foreign company: determine whether it is a CFC, today, before filing the next 1040. Document the analysis.
• If you have a CFC and have not been filing Form 5471: stop reading this and call a tax advisor about delinquent filing procedures. The penalty exposure grows with every passing month.
• If you have a CFC and ARE filing 5471 but never elected Section 962: model the math both ways for the current year. The election is made on the return and is annual.
• If you are designing a foreign entity structure now: evaluate check-the-box vs. CFC-with-962 vs. holding-under-US-C-corp before incorporation, not after. The wrong structure is hard to unwind without triggering deemed distributions.
• If your foreign sub is in a low-tax or no-tax jurisdiction (Cayman, BVI, UAE, Bermuda, Bahamas): GILTI will hit hard regardless. Section 962 helps but the FTC has nothing to credit against. Reconsider whether the structure is worth the US tax cost.
• If you live in California: add the state tax to every model. California does not follow the federal Section 250 deduction or treat Section 962 cleanly, so the California cost on GILTI often dwarfs the residual federal cost.

Frequently Asked Questions

Does GILTI apply if I own less than 10% of a foreign company?

No. The CFC analysis and the Subpart F / GILTI inclusions only apply to "US shareholders" who individually own 10% or more by vote or value, applying constructive ownership rules. A 5% angel investor in a foreign startup is not pulled in. The Passive Foreign Investment Company (PFIC) rules can still apply at lower ownership levels for investment-type companies, which is a separate issue covered in our PFIC reporting post.

Do I file Form 5471 even if I owe no US tax?

Yes. Form 5471 is informational reporting. The $10,000 per-form penalty applies for failure to file even when no tax is owed. Many 5471s are filed on returns where there is zero Subpart F, zero GILTI inclusion, and zero distribution. The filing obligation is independent of the tax obligation.

Can I make the Section 962 election retroactively?

Limited. Section 962 is elected on the timely-filed return (including extensions) for the year of the inclusion. Amended-return relief is available in narrow circumstances, but you should not assume you can fix a prior year by amending. Get it right at original filing time.

What if my foreign company has a loss?

A CFC loss does not create a current US deduction for the US shareholder. GILTI is a positive-only calculation: positive tested income from one CFC can be reduced by tested losses from another CFC of the same US shareholder, but a net negative does not flow to your 1040 as a loss. You still file Form 5471 to report the loss.

How does this interact with state tax?

States vary. California taxes GILTI as ordinary income to the individual and does not allow the Section 250 deduction or the deemed-paid FTC under Section 962. Several states (Florida, Texas, Washington, Nevada) have no individual income tax and so do not tax GILTI at the state level. New York and New Jersey have partial conformity. State residency at the time of the GILTI inclusion can materially change your total tax bill, which is one reason where you live and where you incorporate matter for international structures.

Is there a small-business exemption?

Not really. The CFC and GILTI rules apply regardless of the foreign company's size. There is no de minimis exception for low total income. A $50,000-revenue UK Ltd owned 100% by a US founder is fully subject to GILTI and Form 5471 just like a $50 million operating sub. The de minimis thresholds that exist (5% of gross income or $1 million for Subpart F categorization, for example) are narrow technical exceptions, not general small-business carveouts.

When to Talk to Us

International tax for individual founders is one of the highest-stakes, lowest-margin-for-error areas of the code. The penalty regime alone (Form 5471 at $10,000 a pop) means a single missed filing year can cost more than years of professional advice. The substantive tax cost (GILTI at 50%+ all-in without proper planning, single-digit percent with the right elections) means structure choices made before the first dollar of foreign income hits the books are worth far more than cleanup after the fact.

At Silicon Valley Tax we work with Bay Area founders on CFC analysis, Section 962 modeling, check-the-box elections, Form 5471 preparation and delinquent filings, and the broader question of whether the international structure you have is the right one. Most of our international-tax clients come to us either at incorporation (the right time) or after the first IRS notice (the expensive time).

If you own any foreign entity, or you are about to set one up, schedule a free consultation and we will walk through your specific structure, the elections available, and the filings you may already owe. You can also see our full international tax services overview.