Frequently Asked Questions – Xerxes Associates LLP
Welcome to the FAQ section for Xerxes Associates LLP, a leading UK-based tax advisory firm specialising in US and UK cross-border tax services. Whether you’re a US expat living in the UK, a dual citizen, or a UK resident with American income ties, our expert team is here to help. Below, we address some of the most common questions our clients ask, with a focus on tax regulations and reporting requirements as of 2025.
Do I still need to file a US tax return if I live in the UK?
Yes. As of 2025, all US citizens and green card holders are required to file a US tax return annually, regardless of where they live. This obligation applies even if you pay tax in the UK. At Xerxes Associates LLP, we specialise in helping US expats file accurate returns while maximising available exclusions and credits such as the Foreign Earned Income Exclusion and Foreign Tax Credit to avoid double taxation.
How does the US/UK Tax Treaty impact my filing obligations?
The US-UK Double Taxation Treaty allows taxpayers to avoid being taxed twice on the same income. However, it doesn’t eliminate your obligation to file tax returns in both jurisdictions. Our US Tax Advisory and UK Tax Advisory services ensure that the treaty is applied correctly to your personal financial situation.
What is FATCA and do I need to comply with it in 2025?
Yes, FATCA (Foreign Account Tax Compliance Act) remains in full effect in 2025. If you are a US person living in the UK with foreign financial accounts that exceed certain thresholds, you must report those accounts to the IRS using Form 8938. Additionally, banks in the UK are required to report your account information to the US government. Our US Tax Advisory team ensures full FATCA compliance.
Do I need to file an FBAR (Foreign Bank Account Report)?
If you are a US taxpayer with combined foreign accounts exceeding $10,000 at any point in the year, you are required to file an FBAR (FinCEN Form 114). This applies even if the accounts are jointly held or the funds are not yours personally. We assist with accurate FBAR filings as part of our comprehensive cross-border tax service.
Can I be taxed twice on the same income?
In most cases, no. With correct use of the US-UK Double Taxation Treaty, Foreign Tax Credit, and relevant exclusions, we can help you legally reduce or eliminate double taxation. At Xerxes Associates LLP, we create customised solutions to protect your global income from unnecessary tax exposure.
What are the UK tax residency rules in 2025?
The Statutory Residence Test (SRT) remains the main method for determining UK tax residency. It considers the number of days spent in the UK, ties to the country, and employment status. If you’re unsure about your UK residency status, our UK Tax Advisory team can perform a residency analysis and help you understand your obligations under HMRC guidelines.
Is my UK income taxable in the US?
Yes. US citizens are taxed on worldwide income, including salaries, pensions, dividends, and rental income from the UK. However, we can help you claim foreign tax credits or exclusions so that you are not taxed twice. For a full strategy review, explore our US Tax Advisory services.
How do you help with late tax filings?
We provide assistance with late or non-compliant tax filings, including streamlined filing procedures where applicable. If you’ve missed previous filings for your US tax return, FATCA, or FBAR, our team can help you bring your filings up to date without incurring unnecessary penalties. Visit Who We Help to see how we’ve helped clients in similar situations.
Do I need to report my UK pension or ISA to the IRS?
Yes. In 2025, UK pensions and Individual Savings Accounts (ISAs) must be reported on your US tax return. These accounts are often treated differently under IRS rules, and incorrect reporting can trigger audits or penalties. At Xerxes Associates LLP, we ensure that all accounts are reported correctly and in line with the latest US tax laws.
How do I declare a property I own in the UK?
If you’re a US citizen or resident and own UK property, you may need to report rental income, capital gains, or foreign property ownership depending on how the asset is used. Our team can help you navigate property tax rules under both HMRC and IRS jurisdictions. We also provide UK Tax Advisory services for local compliance.
What support do you offer for US taxpayers moving to the UK in 2025?
If you’re relocating to the UK, it’s essential to plan your move with tax implications in mind. We offer pre-arrival planning to help you optimise residency status, investment structures, and income flows. Start with a confidential consultation and learn how our tailored strategies can simplify your transition.
How are your services different from other tax firms?
We are one of the few UK-based tax firms that specialises exclusively in UK and US cross-border tax advisory. Unlike general accounting firms, we provide a focused, high-level service to individuals navigating the complexities of dual taxation. Read more about our approach on the About Us page.
Who do you typically help?
Our clients include:
- US expats in the UK
- UK residents with US filing obligations
- Entrepreneurs and business owners with dual tax exposure
- High-net-worth individuals with international investments
- Dual citizens navigating FATCA and FBAR
To see specific examples of how we’ve supported our clients, visit our Who We Help page.
How can I get started?
We offer a clear, step-by-step process starting with an initial consultation. Once we assess your needs, we prepare a tailored engagement plan outlining key dates, requirements, and deliverables. To begin, contact us through the Contact Us page and one of our advisors will be in touch promptly.
Get in Touch
For those seeking guidance on taxation or other expatriate tax matters, Xerxes Associates LLP offers consultations to discuss individual needs and circumstances. To learn more about their services or to schedule a consultation, visit their contact page.
