What are the precise tax implications for a US citizen starting a business in the UK?

Understanding the tax implications of starting a business overseas can be challenging for aspiring entrepreneurs. When it comes to tax, the landscape becomes even more complex for US citizens looking to establish a company in the United Kingdom. This article will guide you in navigating the maze of domestic and international tax codes and help you understand how your decision to start a business in the UK will impact your tax situation.

Navigating the UK Tax System

Before you kickstart your business in the UK, you must first understand how the UK tax system operates. The UK operates on a residency-based taxation system. This means that once you become a UK resident for tax purposes, you will have to pay UK tax on your worldwide income, including income from your US-based businesses or employment.

UK Corporation Tax

When starting a company in the UK, one of the first taxes you should be aware of is the corporation tax. This is a tax imposed on all profits made by companies based in the UK. At the time of writing, the UK Corporation tax stands at 19%. However, it's crucial to stay updated with the current rate as it can change from year to year.

UK Value Added Tax (VAT)

The Value Added Tax (VAT) is another significant tax consideration when starting a business in the UK. If your company’s annual turnover exceeds the VAT threshold, currently £85,000, you are required to register for VAT. The standard VAT rate is 20%, although some goods and services may be taxed at a reduced rate of 5%, or even zero-rated.

Understanding Your US Tax Obligations

As a US citizen, even if you reside or operate a business overseas, you still have tax obligations back home. The United States operates on a citizenship-based tax system, which means that all US citizens are required to file a US tax return, regardless of their residence or where their income is earned.

US Federal Income Tax

The US federal income tax applies to worldwide income. This means that even if you are running your business in the UK, you are still required to report all your foreign income to the IRS. You will need to file Form 1040, the standard individual income tax return form, each year.

However, the US has provisions in place to avoid double taxation. The Foreign Earned Income Exclusion (FEIE), for instance, allows you to exclude a certain amount of your foreign earned income from US tax. For the 2024 tax year, the FEIE amounts to $112,000.

Foreign Bank and Financial Accounts

If you have a financial interest in or signature authority over a foreign financial account, including a bank account, brokerage account, mutual fund, or other types of foreign financial accounts, and the aggregate value of all foreign financial accounts exceeded $10,000 at any time during the calendar year, you are required to report this to the US Department of Treasury by filing a Financial Crimes Enforcement Network (FinCEN) 114, Report of Foreign Bank and Financial Accounts (FBAR).

Double Taxation Relief

To ease the burden of being subject to tax in two jurisdictions, the US and the UK have a double tax treaty in place. It is essential to understand how these agreements work to ensure you're not paying more tax than necessary.

The US-UK Tax Treaty

The US-UK Tax Treaty is designed to prevent double taxation for individuals who are earning income in both countries. Essentially, this treaty allows taxpayers to offset tax paid in one country against the tax due in the other. In practical terms, this means that tax you pay in the UK can be offset against tax you owe in the US, and vice versa.

Foreign Tax Credit

The Foreign Tax Credit is another method for US taxpayers to avoid being taxed twice on the same income. This tax credit allows you to offset the taxes you paid to a foreign country against your US tax bill. However, claiming the Foreign Tax Credit requires careful planning and paperwork. You will need to file IRS Form 1116, and the tax credit can only be claimed against the same type of income in both countries.

Hiring Employees and Payroll Tax Considerations

Hiring employees in the UK comes with additional tax considerations. As an employer, you will have to contribute to the UK's National Insurance and administer payroll taxes.

UK Payroll Taxes

When you hire employees in the UK, you are required to deduct income tax and National Insurance contributions (NICs) from their salaries and pay these to the UK tax authorities. This system is known as Pay As You Earn (PAYE). The rates of income tax and NICs depend on how much your employees earn.

US Social Security and Medicare Taxes

As a US citizen, you are generally required to pay Social Security and Medicare taxes on your worldwide income, even if you live and work in the UK. However, under the US-UK Totalization Agreement, you can choose to only pay social security taxes to one of the two countries, typically the one where you live and work.

In conclusion, starting a business in the UK as a US citizen involves navigating two tax systems. While this can be complex, understanding the key concepts and requirements can help you plan effectively and minimize your overall tax liability. It's always advisable to seek advice from tax professionals who are experienced in both US and UK tax law to ensure you are compliant and making the most of any available tax benefits.

Utilising Expat Tax Benefits

Navigating the tax systems of two countries can seem daunting, but there are several benefits specifically designed for expatriates. Understanding these benefits can help significantly lower your tax liability.

Foreign Earned Income Exclusion (FEIE)

The FEIE is a crucial benefit for US citizens living abroad. It allows you to exclude a portion of your foreign earned income from US income tax. For the 2024 tax year, the FEIE amounts to $112,000. Any income earned above this threshold is subject to US income tax. To qualify for the FEIE, you must meet the physical presence test (living in a foreign country for at least 330 full days during a 12-month period) or the bona fide residence test (being a bona fide resident of a foreign country for an uninterrupted period that includes an entire tax year).

Foreign Housing Exclusion or Deduction

In addition to the FEIE, US expats can also take advantage of the Foreign Housing Exclusion or Deduction. This allows you to exclude or deduct from your income a certain amount of housing expenses that exceed a base amount. The base amount is 16% of the FEIE. Qualifying expenses include rent, utilities (except telephone), and personal property insurance.

UK-Specific Tax Considerations

Doing business in the UK comes with additional tax responsibilities and implications. Understanding these can help you avoid potential financial pitfalls and take advantage of beneficial provisions.

Capital Gains Tax

In the UK, if you sell a business asset and make a profit, you could be liable to pay Capital Gains Tax. This tax applies to most assets when they're sold, and some when they're gifted or transferred. The tax rate depends on your total taxable income, so it may vary from year to year.

National Insurance

In the UK, National Insurance is a tax on earnings and self-employed profits. Your National Insurance contributions fund welfare state benefits, such as the State Pension and unemployment benefits. If you're self-employed, you pay two types of National Insurance: Class 2 if your profits are £6,515 or more a year, and Class 4 if your profits are £9,569 or more a year.


Starting a business in the UK as a US citizen can be a rewarding venture, but it's vital to stay informed about your tax obligations in both countries. Understanding the intricacies of the UK and US tax systems, how they interact, and what benefits you can utilise can save you money and ensure you're compliant with all necessary regulations. Leveraging expat tax benefits such as the Foreign Earned Income Exclusion and the Foreign Housing Exclusion or Deduction can significantly reduce your US tax liability. At the same time, being aware of UK-specific tax considerations, such as Capital Gains Tax and National Insurance, will help you accurately calculate your UK tax obligations. Remember, it's always wise to seek advice from tax professionals experienced in both US and UK tax law to help you navigate these complexities and make the most of your international business venture.