If you are a US person — citizen, green card holder, or tax resident — who owns or controls a foreign corporation, the IRS has rules designed specifically for you. Controlled Foreign Corporation legislation is not an obscure provision from the fringes of the tax code. It is a foundational framework that affects every US founder who structures offshore operations, and misunderstanding it is one of the most expensive mistakes in international tax planning.

Here is what you need to know before you form an offshore entity — and what to do if you already have one.

What Is a CFC?

A Controlled Foreign Corporation is any foreign corporation in which "US shareholders" own more than 50% of the total combined voting power or total value of the stock. A "US shareholder" for CFC purposes is a US person who owns 10% or more of the foreign corporation's voting stock or value. Attribution rules apply — shares owned by related parties, partnerships, and certain trusts are counted toward the 50% threshold.

Once an entity is classified as a CFC, certain categories of income earned by that entity are taxed to the US shareholders immediately — even if no distributions are made. This is the anti-deferral principle at the core of CFC legislation: offshore income does not get to sit in a foreign entity accumulating tax-free. The IRS wants its share in the year the income is earned, not the year the cash is distributed. Most US founders with offshore companies — regardless of the jurisdiction — have a CFC on their hands.

Subpart F Income: The Original Anti-Deferral Rule

Subpart F income — codified in IRC Sections 951 through 965 — covers specific categories of income that are deemed passive or easily manipulated to shift income offshore. The primary category is Foreign Personal Holding Company Income (FPHCI): dividends, interest, rents, royalties, annuities, and net gains from property and commodity transactions. Also included are Foreign Base Company Sales Income (income from buying goods from or selling goods to a related party outside the CFC's country of incorporation) and Foreign Base Company Services Income (income from services performed for or on behalf of a related party).

When a CFC earns Subpart F income, the US shareholder includes their pro-rata share in US gross income for the tax year — regardless of distribution. A Singapore holding company that earns $500,000 in interest income and dividends from portfolio investments creates immediate Subpart F inclusion for its US shareholders. There is no deferral. The tax is triggered by the earnings, not the cash flow.

GILTI: The Modern Anti-Deferral Regime

The Tax Cuts and Jobs Act of 2017 introduced Global Intangible Low-Taxed Income (GILTI) — a regime that reaches beyond Subpart F and taxes nearly all net income of a US shareholder's CFCs annually. GILTI is calculated as the CFC's net income above a 10% return on Qualified Business Asset Investment (QBAI) — essentially the depreciable tangible assets of the CFC. Income attributable to real tangible assets is partially sheltered; income in excess of that return is subject to GILTI inclusion.

For corporate US shareholders, the net GILTI rate is 10.5% (after the 50% GILTI deduction applied against a 21% corporate rate), rising to 13.125% after 2025. For individual US shareholders, the situation is considerably worse: absent a Section 962 election, GILTI is taxed at ordinary income rates — up to 37%. Individual founders with offshore operating companies frequently face a far higher effective GILTI rate than their corporate counterparts, and this asymmetry is not widely understood at the time of structure formation. The Section 962 election allows individuals to elect to be taxed as if they were a domestic corporation for GILTI purposes, providing access to the 50% GILTI deduction and the indirect foreign tax credit. It is one of the highest-value planning elections available to individual CFC shareholders, and it is frequently overlooked.

The GILTI High-Tax Exclusion

Regulations provide a GILTI high-tax exclusion (HTE) that allows US shareholders to elect to exclude from GILTI any income item that bears a foreign effective tax rate above 18.9% — currently 90% of the 21% US corporate rate. For founders with Singapore entities taxed at 17%, the calculation is close to but below the threshold: Singapore's 17% rate does not automatically trigger the exclusion, which begins at 18.9%.

However, the HTE applies at the level of individual "tested units" within the CFC structure — not at the aggregate CFC level. Careful attention to how income streams are categorized and how the effective rate is calculated for each tested unit can affect whether the exclusion applies and to which income. For UAE free zone entities at 0%, no exclusion is available and GILTI applies to the full net income. Planning the interaction of local effective tax rates and the HTE threshold is a core component of GILTI-aware CFC structuring for US founders.

Practical Planning Steps

First, identify CFC status before forming the entity. If you are a US person forming a foreign company in which you will own 10% or more, CFC analysis is not optional — it is the first question your advisor should address before incorporation documents are signed. Knowing whether your structure will be a CFC changes the entity choice, the jurisdiction selection, and the income planning that follows.

Second, analyze income streams for Subpart F categories before the entity begins operations. Royalties, interest income, and certain dividend flows are Subpart F inclusions regardless of GILTI. Structuring to minimize Subpart F categories requires attention to the nature of transactions between the CFC and related parties.

Third, model the GILTI impact for the anticipated income of the structure and determine whether a Section 962 election is appropriate. For individual founders expecting significant CFC income, this analysis should be completed in year one — not after the first year's returns reveal an unexpected liability. Fourth, establish proper Form 5471 filing for each CFC from year one. Penalties for failure to file begin at $10,000 per form, per year, and escalate. Catching up on multiple years of missing filings is expensive and time-consuming.

When You Need a Tax Attorney vs. a Structuring Advisor

A structuring advisor — a firm like Apex Advisory — can identify the right jurisdictions, entity types, and architecture for your business and investment objectives. They can model the income flows, recommend whether a Singapore or UAE structure fits your specific situation, advise on what substance requirements apply, and design a structure that works commercially and positions you favorably for tax purposes.

A US tax attorney specializing in international tax is essential for the compliance layer: Form 5471 preparation and review, Subpart F and GILTI analysis, Section 962 elections, PFIC analysis for any investment holdings, and FBAR and FATCA compliance. These are not advisory functions — they are legal compliance obligations with penalties that escalate quickly and that carry statute of limitation implications. The two roles are complementary, not interchangeable. The founders who get into serious trouble are those who hired one without the other.