FEIE vs Foreign Tax Credit for US Expats in the UK: Which Strategy Saves More?

The Core Question: FEIE or Foreign Tax Credit?

US expats working in the UK face a unique tax challenge: you're taxed on worldwide income by the United States, and on UK-sourced income by HM Revenue & Customs. The good news is that US law provides two primary mechanisms to avoid double taxation. The Foreign Earned Income Exclusion (FEIE) lets you exclude roughly the first $120,000 of earned foreign income from US federal tax (the exact figure changes annually). The Foreign Tax Credit (FTC) lets you claim a dollar-for-dollar credit against your US tax liability for UK income taxes paid. Which one saves you more depends on your income level, UK tax rate, and whether you have passive income—and the answer is rarely obvious without a detailed calculation.

Understanding the Foreign Earned Income Exclusion (FEIE)

The FEIE is codified in Internal Revenue Code Section 911 and allows qualifying US citizens and residents abroad to exclude foreign earned income—wages, self-employment income, bonuses—from US federal income tax, provided you meet the Physical Presence Test or Bona Fide Residence Test.

Who Qualifies?

You must satisfy one of these tests:

• Physical Presence Test: You are outside the US for at least 330 days in a 12-month rolling period. Days do not have to be consecutive.
• Bona Fide Residence Test: You are a resident of the UK under its laws for an uninterrupted tax year.

Most UK-based expats rely on the Physical Presence Test because it is more straightforward and doesn't require formal residency status.

The Exclusion Amount

The maximum excludable amount is adjusted annually for inflation. For recent tax years, the figure has hovered around $120,000, but you must confirm the current-year threshold with the IRS Foreign Earned Income Exclusion page.

Key Limitations

• Earned income only: Dividends, capital gains, pension withdrawals, interest, and rental income do not qualify for the FEIE.
• Housing exclusion/deduction: You may also exclude or deduct housing costs above a baseline, but this is complex and requires separate calculation.
• Self-employment tax: Even if you exclude earned income under FEIE, you still owe US self-employment tax on that income (approximately 15.3% on 92.35% of net self-employment income).
• State taxes: FEIE applies only to federal income tax; some US states may still tax foreign earned income.

Understanding the Foreign Tax Credit (FTC)

The FTC is outlined in Internal Revenue Code Sections 901–908 and allows you to claim a credit—not a deduction—for income taxes paid to the UK on income that is also taxable to the US.

How It Works

The FTC is calculated as follows:

1. Determine your total worldwide income taxable to the US.

2. Calculate your tentative US federal income tax on that income.

3. Calculate the foreign tax credit limitation: (Foreign Source Income ÷ Worldwide Income) × US Tax = Maximum Allowable Credit.

4. Your credit is the lesser of UK tax paid or the limitation.

If your UK tax exceeds the limitation, the excess is generally lost (though there is a carryback and carryforward mechanism).

Key Advantages

• Applicable to all income types: Unlike FEIE, the FTC covers earned income, passive income, capital gains, and more.
• No income cap: There is no upper limit on how much FTC you can claim (subject to the limitation formula).
• Preserves US tax credits: You retain eligibility for US child tax credits, education credits, and other non-refundable credits.

Key Limitations

• The limitation formula: If your UK tax rate is lower than the US federal rate (currently 37% at the top), you may lose some credit.
• Creditable taxes only: Only income taxes count; VAT, National Insurance, stamp duty, and other indirect taxes do not qualify.
• Carryback and carryforward: Excess credit can be carried back one year or forward ten years, but this adds complexity.

Comparing the Two: A Practical Framework

When FEIE Typically Wins

• Lower to mid-range earners earning £40,000–£90,000 (roughly $50,000–$115,000): Your UK income tax is lower than the US marginal rate, so the FTC limitation would disallow part of your UK tax. FEIE avoids this.
• Self-employed with modest income: FEIE excludes your earned income from federal tax; you pay only self-employment tax on the excluded amount.
• No passive income: If all your income is earned and you are under the FEIE ceiling, you avoid nearly all US tax.

Example: Sarah earns £60,000 as an employee in London. Her UK income tax is approximately £8,000. Under FEIE, she excludes £60,000 (within the ~$120,000 threshold) and owes no US federal income tax. Under FTC, her US tax on £60,000 worldwide income would be roughly $10,000, but the FTC limitation allows her to credit only ~$8,000, leaving a $2,000 federal bill. FEIE saves her ~$2,000.

When the Foreign Tax Credit Typically Wins

• Higher earners earning above the FEIE ceiling: Once you exceed ~$120,000, FEIE caps your exclusion, and the FTC applies to excess income. If your UK tax rate approaches or exceeds the US marginal rate, the FTC limitation allows you to credit most or all UK tax paid.
• Significant passive income: If you have UK rental income, dividends, or capital gains, FEIE does not help. The FTC covers all income types.
• Multiple sources of foreign income: If you work in the UK but have rental income in Germany, or consulting income from Canada, the FTC can absorb taxes paid to multiple countries, subject to the limitation.
• US tax credits matter: If you claim the Child Tax Credit, Earned Income Tax Credit, or education credits, electing FEIE may reduce your ability to use them (though the statute has nuances). The FTC preserves these credits.

Example: James earns £150,000 as a director in London, generating approximately £35,000 in UK income tax. The first ~$120,000 of his income is covered by FEIE, but the remaining ~$30,000 is subject to US tax. His US tax on £150,000 would be roughly $48,000, but his FTC limitation allows him to credit the full £35,000 (roughly $43,000), leaving only ~$5,000 owed. FTC is more efficient for his high income.

A Nuanced Reality: The Election

Crucially, you do not have to choose one or the other permanently. You can elect FEIE on your Form 2555 (Foreign Earned Income Exclusion) and still claim FTC on certain income types (for example, FEIE on salary, FTC on a passive rental gain). However, once you elect FEIE, you cannot use it for earned income in the same tax year and a future tax year without also adopting it for the intervening years—except if you revoke the election with IRS consent. Consult a licensed tax professional before making an election, as revoking it requires Form 8833 or a private letter ruling.

Cross-Border UK-US Complications

Timing Differences

The UK and US have different tax years (UK: 6 April to 5 April; US: 1 January to 31 December) and different tax rules. An event in the UK tax year 2023/24 may span two US tax years, creating mismatch. This requires careful income allocation when calculating the FTC limitation.

National Insurance

UK National Insurance (both employee and employer contributions) does not qualify for the FTC, as it is not an income tax. If you are an employee in the UK, your employer typically pays ~15% National Insurance on your salary. This is an additional cost not creditable in the US, which can make the FTC less attractive than it first appears.

Residency and State Tax

If you have not been abroad for the full tax year, or if you remain a bona fide resident of a US state, you may owe state income tax on worldwide income. Neither FEIE nor FTC can fully shield you from state tax in every case. Some states (Texas, Florida, Wyoming) have no state income tax; others (New York, California) tax residents on worldwide income regardless of FEIE or FTC.

The Missed Return Trap

If you have not filed US returns for prior years while abroad, you may be exposed to penalties and interest—even if tax law would eventually owe you a refund. The IRS Streamlined Filing Compliance Procedures can help you catch up safely, but there are strict eligibility rules. This is where professional guidance is essential; learn more about catching up on missed US tax returns.

How to Model Your Own Scenario

Here is a simplified process:

1. Gather UK tax information: Obtain your UK tax return (Self Assessment tax return or employer's payslip, P60, and tax code). Calculate total UK income tax and National Insurance paid.

2. Calculate US tax under FEIE:

• Determine whether you meet the Physical Presence or Bona Fide Residence Test.
• Exclude earned income up to the current threshold (~$120,000).
• Calculate US federal tax on any excess and passive income.
• Factor in self-employment tax if you are self-employed.

3. Calculate US tax under FTC:

• Report all worldwide income on your US return.
• Calculate US federal tax on the full amount.
• Calculate the FTC limitation (Foreign Source Income ÷ Worldwide Income × US Tax).
• Claim the lesser of UK tax paid or the limitation as a credit.

4. Compare net US tax liability under each scenario.

5. Consider state tax: Factor in any state income tax owed.

This exercise often reveals that the best choice depends on your specific income, tax rate, and family circumstances. A licensed CPA or EA with cross-border experience can model both scenarios accurately and advise on the election strategy that minimizes your total tax burden.

Why Professional Guidance Matters

The FEIE and FTC calculation looks straightforward in an outline, but real-world situations introduce complexity:

• Income timing: Does your employer pay you in GBP or USD? When is income recognized for US purposes?
• Deductions and credits interaction: How do FEIE and education credits interact? Can you claim the Earned Income Tax Credit if you elect FEIE?
• Form 2555 Line 45 calculation: The proration of expenses and the housing exclusion/deduction require precise record-keeping.
• State and local taxes: Some states offer credits for foreign tax paid; others do not. Your domicile status matters.
• Future years: Your choice this year may constrain your options next year if you revoke FEIE.

Every US expat's situation is distinct. A licensed CPA or Enrolled Agent in the US, or a chartered accountant with US-UK cross-border expertise, will review your income, anticipated tax, UK compliance position, and personal circumstances to recommend the strategy that saves the most.

If You Are Behind on US Returns

If you have been working in the UK for several years and have not filed US returns, do not panic—but do act promptly. The IRS has a Streamlined Filing Compliance Procedures program that allows eligible expats to catch up on back returns with reduced penalties, provided you meet strict residency and good-faith criteria. However, missing returns also mean you have not benefited from FEIE, potentially resulting in years of overpaid US tax. Learn more about the process and your options on our dedicated page for missed US tax returns, where we walk you through eligibility and the filing process.

Next Steps

Choosing between FEIE and FTC is not a one-size-fits-all decision. Your optimal strategy depends on your income level, the composition of that income (earned vs. passive), your UK and US tax rates, family circumstances, and whether you have any state tax exposure.

If you are a US expat in the UK—or any other country—we recommend a professional tax review before filing. Our team of licensed CPAs and EAs specializes in cross-border returns for US citizens abroad. We model both FEIE and FTC scenarios, factor in UK compliance, and identify the election strategy that minimizes your tax bill.

Book a confidential consultation with one of our specialists today. We'll review your income, discuss your circumstances, and provide a clear recommendation backed by detailed calculations—all signed off by a licensed professional.

Frequently asked questions

Can I use both FEIE and FTC in the same tax year?

Not fully. Once you elect FEIE for earned income, you cannot claim FTC for that earned income in the same year. However, you can elect FEIE for earned income and claim FTC for passive income (e.g., rental income, capital gains) in the same year. Revoking FEIE in future years requires IRS consent and can trigger a multi-year election lock.

Does the Foreign Tax Credit cover UK National Insurance?

No. National Insurance is not an income tax and does not qualify for the FTC. Only income taxes (personal income tax, corporation tax withholding, and certain other direct taxes) are creditable. This is one reason FTC can be less valuable than it first appears for UK employees.

What is the physical presence test exactly?

You must be outside the United States for at least 330 days during a 12-month rolling period (any 12 consecutive months; not a calendar year). Days abroad do not have to be consecutive. Brief trips home (e.g., a one-week holiday) are not counted as US presence if you intended to return abroad.

If I earn over $120,000, is FEIE useless?

No. You can still exclude the first ~$120,000 under FEIE and apply FTC to income above that threshold. The combined strategy is often optimal for high earners. Additionally, the housing exclusion/deduction—a separate benefit tied to FEIE—may reduce taxable income further, depending on your housing costs in the UK.

Do I need to file a UK tax return if I claim FEIE on my US return?

Yes. FEIE is a US tax benefit only; it does not affect your UK tax obligations. HMRC requires UK residents to file a Self Assessment return if they have earned income or other reportable activity. Filing the UK return accurately ensures you pay the correct amount due, which you then use to calculate your US FTC limitation.