The controlled foreign corporation (CFC) rules were written with one goal in mind: stopping U.S. taxpayers from parking income in a low tax country and putting off U.S. tax indefinitely. Getting them wrong is costly. A surprise Subpart F inclusion, unplanned GILTI exposure or a missed Form 5471 can easily run into tens of thousands of dollars.
Below, we walk through how a CFC is defined, how the IRS taxes its income under Subpart F, GILTI and Section 956, which planning tools can shrink the bill, and how other countries handle the same issue.
Key Takeaways
- A foreign corporation is a CFC when U.S. shareholders who each own at least 10% together hold more than 50% of the vote or value
- U.S. shareholders are taxed every year on Subpart F and GILTI income, distributed or not
- A Section 962 election or the GILTI high tax exclusion can reduce, and sometimes wipe out, U.S. tax on CFC income
- Many countries, including the UK, Germany, Japan and Australia, have CFC regimes of their own
What Is a Controlled Foreign Corporation?
IRC Section 957 says a foreign corporation is a CFC if U.S. shareholders together own more than 50% of its total combined voting power, or more than 50% of the total value of its stock, on any day of the tax year. Notice the words "any day." A company can move in and out of CFC status during the year, and each day is tested on its own.
Not every U.S. owner is counted. Under IRC Section 951(b), a "U.S. shareholder" is a U.S. person who owns at least 10% of the corporation's vote or value. That 10% test does double duty: it decides who has to report the company's income, and it decides whose stock gets added up when testing for CFC status.
Ownership Thresholds and Attribution Rules
Shares in your own name are only part of the picture. The IRS looks at three kinds of ownership:
- Direct ownership: stock you or your company hold outright
- Indirect ownership: stock held through a foreign entity you own
- Constructive ownership: stock treated as yours because a family member, partnership or option holder owns it
The Tax Cuts and Jobs Act of 2017 removed the old limit on "downward attribution" in IRC 958(b)(4). That change widened who counts as a CFC and who counts as a U.S. shareholder, and it pulled some foreign owned groups with very little U.S. connection into CFC status.
Two simple examples show how the math works:
- Six unrelated owners at 9% each: nobody reaches the 10% shareholder test, so the company isn't a CFC, even though the six of them own 54% together.
- Three owners at 20% each: each one passes the 10% test, and together they hold 60%. That company is a CFC.
Why CFC Rules Exist
Before Subpart F, a U.S. taxpayer could set up a corporation in a tax haven, book income there and just never bring the money home. As long as the cash stayed abroad, U.S. tax could be put off for years or forever. The CFC rules shut that door by taxing certain kinds of foreign corporate income to U.S. shareholders in the year it's earned, not the year it's paid out.
How the IRS Taxes Controlled Foreign Corporation Income
The idea behind CFC taxation is straightforward. Some categories of income are taxed to the U.S. shareholder right away, whether or not the CFC ever declares a dividend. Three sets of rules decide what falls into that category.
Subpart F Income
Subpart F income is mostly passive or easily moved income, defined in IRC Sections 952 through 954. It includes:
- Dividends, interest, rents and royalties
- Insurance income
- Certain sales and services income involving related parties
There's a de minimis rule for foreign base company income and insurance income added together:
- If the total is below the lesser of 5% of gross income or $1 million, none of it is treated as Subpart F income
- If it's above that level, the whole amount is taxable
- If it's above 70% of gross income, all of the CFC's income can be swept in under the full inclusion rule
Global Intangible Low Taxed Income (GILTI)
The 2017 Tax Cuts and Jobs Act created GILTI to reach active foreign business income that Subpart F didn't touch. For tax years beginning before 2026, GILTI was a shareholder's net CFC tested income minus a 10% deemed return on Qualified Business Asset Investment (QBAI).
That formula has now changed. The 2025 tax law renamed GILTI net CFC tested income (NCTI) and dropped the QBAI exclusion for tax years beginning after December 31, 2025. In plain terms, the 10% routine return carve out is gone, and almost all of a CFC's tested income now goes into the calculation.
Section 956: Investment in U.S. Property
Section 956 goes after a different move: using CFC earnings for a U.S. shareholder's benefit without paying a formal dividend. When a CFC invests in U.S. property, the investment can be treated as a deemed dividend. Typical examples:
- A loan to its U.S. shareholder
- Buying stock in a U.S. company
- Running a U.S. branch
Individuals feel this one most. Corporate shareholders can often offset the inclusion with a hypothetical Section 245A deduction. Individuals can't.
Without a Section 962 election, an individual pays ordinary rates on the inclusion (as high as 37% for the 2025 tax year, according to the IRS), with no Section 250 deduction and no access to the foreign tax credit. If you're an individual shareholder and your CFC is thinking about lending you money or buying U.S. assets, plan for the tax before the deal happens.
Tax Planning Strategies to Reduce CFC Tax Exposure
Once you know you own a CFC, the useful question is how much its income will really cost you. A few tools can change that number.
The Section 962 Election
Under Section 962, an individual U.S. shareholder can choose to be taxed on Subpart F and GILTI inclusions as though they were a domestic corporation. That opens up two benefits individuals normally don't get:
- The Section 250 deduction against net CFC tested income
- A limited foreign tax credit for tax the CFC already paid overseas
The tradeoff: when that income is later distributed, the distribution is taxed again to the extent it exceeds the U.S. tax you already paid under the election. It postpones tax and lowers it in the meantime. It does not make the income permanently tax free.
The GILTI High Tax Exclusion
If your CFC operates somewhere with a meaningful corporate tax, the GILTI high tax exclusion (HTE) may take its income out of the calculation altogether. To qualify, the effective foreign tax rate must be greater than 18.9%, which is 90% of the 21% U.S. corporate rate.
You can't apply it to one company and skip the rest. The election binds every U.S. shareholder and has to apply consistently across the CFC group, so it needs to be modeled for the group as a whole.
Restructuring and Timing
Some owners can reduce or eliminate CFC exposure with structural changes, such as:
- Changing ownership percentages so no single U.S. person reaches 10%
- Reorganizing entity layers so attribution rules apply differently
- Timing distributions or acquisitions around the dates when ownership is measured
Which route makes sense depends a lot on where the CFC does business:
| Foreign Tax Rate | Likely Best Fit |
|---|---|
| High (above 18.9%) | GILTI high tax exclusion |
| Moderate | Section 962 election |
| Low | A mix of approaches and several elections |
Doing things in the wrong order can cost more than doing nothing. Electing HTE without checking group consistency, or making a 962 election without projecting the tax when the money is eventually distributed, are two common examples.
At Assured Financial Services, CFC planning runs all year rather than happening at filing time. We work with business owners and expats to test each election against the foreign tax rates they actually pay and settle on a plan before the year closes.
Controlled Foreign Corporation Rules Around the World
The U.S. isn't the only country that taxes offshore corporate income. Many others have rules aimed at the same thing: profits moved to low tax countries to avoid tax at home.
| Country | How it works |
|---|---|
| United Kingdom | Taxes a UK company on its share of profits from nonresident companies it controls, with exemptions for low profit or low margin situations |
| Germany | Attributes passive CFC income taxed below 15% abroad |
| Japan | Includes undistributed profits of related foreign corporations in low tax countries |
| Australia | Attributes passive ("tainted") income of foreign companies controlled by Australian residents |
| New Zealand | Generally attributes passive income; control can mean five or fewer residents holding over 50%, or one resident holding at least 40% |
| Brazil | Applies to controlled and affiliated entities taxed below a threshold of roughly 20% |
| Sweden | Taxes owners of foreign entities taxed below roughly 11.8% |
Most of these systems have three things in common:
- An ownership test, often around 50%
- A focus on passive or mobile income
- A minimum foreign tax rate test
That's by design. The OECD's BEPS Action 3 report set out a common framework for CFC rules in 2015, and many countries have built on it since.
If you own companies in several countries, this overlap is a real concern. The same income can be pulled into the tax base of more than one country at the same time.
Compliance and Reporting Requirements
U.S. shareholders who meet the CFC ownership tests generally have to file Form 5471 every year. The form reports income inclusions, ownership changes and the CFC's earnings and profits. There are five filer categories, based on your ownership percentage, your role as an officer or director, and whether you acquired, sold or simply held CFC stock during the year.
Missing it is expensive. Per the IRS's Form 5471 instructions:
- $10,000 per foreign corporation, per year, for failing to file
- Another $10,000 for each 30 day period the form remains unfiled after the first 90 days following an IRS notice, up to $50,000 more
- A reduction in foreign tax credits if the failure continues
These problems often come to light years later, during an audit or when someone pulls together their foreign holdings for a bank or a visa application. By then, there may be penalty notices to deal with as well as late forms. Assured Financial Services is led by an IRS Enrolled Agent with unlimited practice rights before the IRS. Our U.S. team handles this work in house: tracking Subpart F and GILTI inclusions, preparing Form 5471, cleaning up past compliance gaps, and, when the IRS has already assessed penalties, pursuing abatement and resolving the balance. That tax resolution work pairs well with our fractional CFO support for owners who run foreign subsidiaries and want the structure reflected in their cash planning and forecasts.
Frequently Asked Questions
What is a controlled foreign company?
It's a business registered in one country but more than 50% owned by shareholders from another. Because of that ownership, the shareholders' home country can apply its anti deferral rules and tax some of the company's income right away.
How do I know if a company is a CFC?
Ask one question: on any day of the tax year, did U.S. shareholders who each own at least 10% hold more than 50% of the company's vote or value combined? If the answer is yes, it's a CFC.
What are controlled foreign company rules?
They're rules that make shareholders report and pay tax now on certain foreign corporate earnings, even if nothing is distributed. Their purpose is to stop people from putting off home country tax by leaving income offshore.
Which countries have CFC rules?
The U.S., UK, Germany, Japan, Australia, New Zealand, Brazil and Sweden all have them, along with many others. Since 2015, OECD BEPS guidance has pushed many of these systems toward a similar design.
What is the difference between Subpart F income and GILTI?
Subpart F reaches specific kinds of passive and mobile income, like dividends, interest and royalties. GILTI (now called NCTI) reaches the broader active business income that Subpart F leaves out.
Do I need to file Form 5471 if I own a controlled foreign corporation?
Most U.S. shareholders who meet the CFC ownership tests must file Form 5471 each year. The filer category depends on your ownership level and what happened during the year, so check your situation with a tax professional before the deadline.
