For U.S. multinational companies and individual shareholders of controlled foreign corporations (CFCs), navigating the U.S. international tax system can be complex. Two critical concepts that often overlap are GILTI (Global Intangible Low-Taxed Income) and Subpart F income—both designed to prevent profit shifting to low-tax jurisdictions. Alongside these, the Foreign Tax Credit (FTC) serves as a mechanism to avoid double taxation. Understanding how these regimes interact is essential for accurate tax planning and compliance.
What Is the Foreign Tax Credit (FTC)?
The Foreign Tax Credit allows U.S. taxpayers to offset income taxes paid to foreign governments against their U.S. tax liability on the same income. In other words, if a U.S. corporation or individual pays taxes to another country, they can claim a credit to reduce their U.S. tax owed, preventing double taxation.
However, the FTC is not unlimited—it is subject to specific limitations, generally capped at the proportion of U.S. tax attributable to foreign-source income. The IRS requires separate calculations for different “baskets” of income, such as general, passive, GILTI, and foreign branch income. This ensures that credits from one type of income cannot be used to offset taxes on another.
Understanding GILTI: Global Intangible Low-Taxed Income
The GILTI regime, introduced by the Tax Cuts and Jobs Act (TCJA) of 2017, targets profits earned by U.S. shareholders of CFCs that are considered low-taxed. The idea is to discourage U.S. companies from shifting profits to subsidiaries in low-tax jurisdictions.
GILTI is calculated annually as the shareholder’s pro rata share of the CFC’s income that exceeds a 10% return on tangible assets (known as Qualified Business Asset Investment, or QBAI). This income is included in the U.S. shareholder’s gross income, regardless of whether it is distributed.
To soften the impact, corporate taxpayers are allowed certain deductions and credits:
- A 50% deduction (Section 250) for GILTI inclusions, effectively reducing the tax rate on GILTI income.
- A Foreign Tax Credit (up to 80%) for foreign taxes paid on GILTI income.
However, this FTC is limited to 80% of the foreign taxes and cannot be carried forward or backward, unlike credits in other baskets. This rule creates a partial double taxation effect when foreign taxes are high but exceed the credit limitation.
What Is Subpart F Income?
Subpart F was introduced decades before GILTI, under the 1962 Revenue Act, as a means to curb tax deferral by U.S. corporations with offshore subsidiaries. It requires certain types of passive or easily movable income earned by a CFC—such as dividends, interest, rents, and royalties—to be included in the U.S. shareholder’s income in the year earned, even if not repatriated.
Unlike GILTI, Subpart F income typically represents specific categories of income that the IRS considers prone to abuse. These include:
- Foreign personal holding company income (passive income like interest or dividends)
- Foreign base company sales or services income
- Insurance income earned outside the U.S.
For Subpart F, 100% of foreign taxes paid on that income are eligible for the FTC (subject to general limitations). Credits can also be carried forward 10 years or back one year, making it more flexible than the GILTI basket.
Interaction Between GILTI, Subpart F, and the Foreign Tax Credit
While both GILTI and Subpart F aim to tax foreign earnings currently (instead of deferring them), their interaction with the FTC differs substantially.
- Separate FTC Baskets:
Post-TCJA, the U.S. tax code created distinct FTC baskets for GILTI and other income types. This separation prevents taxpayers from cross-offsetting—meaning excess FTCs from high-tax Subpart F income cannot offset GILTI liabilities. Each category must be calculated independently. - Credit Limitation Differences:
For Subpart F, taxpayers may claim a full FTC (subject to normal limits) and carry unused credits forward. In contrast, GILTI credits are capped at 80% and cannot be carried over. This creates a disparity, especially for companies operating in higher-tax jurisdictions, where foreign taxes might exceed the effective U.S. tax on GILTI. - Deduction Interaction:
The Section 250 deduction reduces the GILTI inclusion amount by 50% (potentially lowering the effective rate to around 10.5%). While this helps reduce U.S. tax liability, it also lowers the FTC limitation, since the credit is proportional to the U.S. tax attributable to GILTI income. - High-Tax Exception Rules:
The IRS introduced the GILTI High-Tax Exclusion (HTE) in 2020, allowing taxpayers to exclude GILTI income already subject to a foreign effective tax rate above 90% of the U.S. corporate rate. Subpart F income has a similar high-tax exception. When applied, such income is excluded from the GILTI or Subpart F category, effectively avoiding U.S. taxation and FTC complications.
Strategic Considerations for Taxpayers
Managing GILTI, Subpart F, and FTC interactions requires careful tax planning. Here are several strategies and considerations:
- Entity Structure Optimization
Multinationals may consider consolidating or reorganizing CFCs to align foreign tax rates and maximize credit utilization. For example, combining high- and low-tax subsidiaries under a single jurisdiction could smooth the overall effective rate. - Timing of Income and Expense Recognition
Since GILTI and Subpart F inclusions occur annually, timing foreign income or expense recognition can affect FTC eligibility and limitation calculations. Planning distribution timing may also influence the ability to apply high-tax exclusions. - Electing the High-Tax Exclusion
Opting for the GILTI High-Tax Exclusion may simplify compliance for subsidiaries in high-tax jurisdictions, removing them from the GILTI regime and eliminating the need to compute FTCs on those earnings. - Monitoring Local Tax Changes
Because the FTC depends on foreign tax paid, changes in foreign tax rates or incentives (such as tax holidays or credits) can materially affect the FTC calculation and residual U.S. tax liability. - Use of Hybrid Entities and Check-the-Box Elections
The treatment of foreign entities for U.S. tax purposes can determine whether income falls into the GILTI or Subpart F basket. Strategic elections under the “check-the-box” rules can alter how income is categorized and how FTCs apply.
The Impact of Pillar Two and Global Minimum Tax
The introduction of the OECD’s Global Minimum Tax (Pillar Two) adds another layer of complexity. This 15% minimum effective tax rate for multinational enterprises may affect GILTI computations and the related FTC availability. U.S. rules have not yet been fully harmonized with Pillar Two, leading to potential mismatches in credit recognition and timing. Taxpayers will need to track how the U.S. Treasury aligns GILTI and FTC rules with global standards.
Conclusion
The interplay between the Foreign Tax Credit, GILTI, and Subpart F income forms one of the most intricate areas of U.S. international taxation. While the FTC remains a crucial relief mechanism against double taxation, its practical effectiveness depends heavily on the specific income category, jurisdictional tax rates, and corporate structure.
Understanding these distinctions—and planning proactively—can help taxpayers minimize double taxation, optimize their FTC utilization, and ensure compliance with both U.S. and foreign tax regulations. As global tax systems continue to evolve with initiatives like Pillar Two and ongoing U.S. reform proposals, staying informed and agile in strategy will remain essential for multinational tax efficiency.