The tax implications for businesses in the US versus the UK involve several key differences in corporate tax rates, income tax structures, and other tax-related considerations. As at 12th August 2024:

1. Corporate Tax Rates:

• UK: The main corporate tax rate is 25% for companies with profits exceeding £250,000. There is a reduced rate of 19% for companies with profits up to £50,000, with a sliding scale for profits between these amounts[1][5].
• US: The federal corporate tax rate is a flat 21% due to the Tax Cuts and Jobs Act of 2017. However, state corporate taxes vary, adding complexity and potentially increasing the overall tax burden[3].

2. Income Tax Structures:

• Both the UK and the US employ progressive income tax systems, but they differ in structure. The UK has fewer brackets, with rates ranging from 0% to 45%, while the US has seven brackets with rates from 10% to 37%[4].
• The UK offers a personal allowance, which is a tax-free income threshold, whereas the US standard deduction serves a similar purpose[1][4].

3. State and Local Taxes:

• In the US, state and local taxes can significantly impact the overall tax burden, with some states having no income tax and others, like California, imposing high rates[4].
• The UK does not have state-level income taxes, which simplifies the tax system compared to the US[4].

4. Value-Added Tax (VAT) vs. Sales Tax:

• The UK imposes a VAT on goods and services, while the US uses a sales tax system that varies by state and locality[3].

5. Special Tax Regimes and Incentives:

• Both countries offer various tax incentives and special regimes, such as R&D credits in the US and lower tax rates for patent income in the UK[3][5].

Overall, while the US offers a lower federal corporate tax rate, the addition of state taxes and the complexity of the tax system can increase the overall tax burden. In contrast, the UK has a more straightforward national tax system but with higher corporate tax rates for larger companies. Businesses must consider these factors when planning operations in either country.

Citations:
[1] https://brighttax.com/blog/taxes-in-uk-vs-us/
[2] https://fullfact.org/economy/corporation-tax-uk-vs-usa/
[3] https://www.taxesforexpats.com/country-guides/uk/uk-vs-us-taxes.html
[4] https://internationaltaxesadvice.com/us-vs-uk-income-tax-rates/
[5] https://taxsummaries.pwc.com/united-kingdom/corporate/taxes-on-corporate-income