US–UK Cross-Border Tax
This is the core of the practice: the places where the US and UK systems overlap, contradict each other, or quietly penalise the unwary. One firm preparing both sides means the strategy is coherent by construction.
The US–UK tax treaty
How the 2001 US–UK income tax treaty allocates taxing rights, why the saving clause limits it for US citizens, where it genuinely helps — pensions, Social Security, dividends, tie-breakers — and when Form 8833 disclosure is needed.
Learn moreDouble taxation relief
The credit mechanism that stops most US–UK double taxation, the timing mismatch between the calendar year and the April UK tax year, income the two systems characterise differently, and the cases where double tax genuinely happens.
Learn moreDual residency
How the US and UK can both treat you as tax resident at once, how the treaty tie-breaker in Article 4 resolves it, why the UK's Statutory Residence Test and US citizenship-based taxation answer different questions, and why 'am I resident?' has several answers.
Learn moreDual citizens
What US–UK dual citizenship means for tax: two worldwide systems at once, the false beliefs that cause the most damage, FATCA friction with UK banks and brokers, and how elections, credits and account choices keep two systems from compounding.
Learn moreMoving to the UK
US-to-UK move planning: the 4-year FIG regime for new arrivals, what to review in US accounts and funds before UK residence begins, breaking state tax residence, and how the first year's split-year and dual filings fit together.
Learn moreMoving to the US
UK-to-US move planning: when US residency actually starts under the substantial presence and green card tests, why ISAs lose their shelter and UK funds become PFICs, handling UK departure and split year, and timing gains around the start date.
Learn morePensions (US–UK)
How the treaty handles pensions both ways: 401(k)s, IRAs and Roths for UK residents, SIPPs and workplace pensions on US returns, employer contributions, the periodic-versus-lump-sum distinction, and the tax-free lump sum mismatch.
Learn moreISAs & investments
Why ISAs are not tax-free to the IRS, how funds inside a stocks and shares ISA fall into the PFIC regime, the mirror problem of US funds without HMRC reporting status, and what US persons in the UK commonly hold instead.
Learn moreProperty (US–UK)
Cross-border property for US–UK taxpayers: rental income reported to both countries, currency gains on sale and on mortgage redemption, the UK's 60-day CGT reporting against annual US reporting, and the main-residence relief mismatch.
Learn moreSocial Security & State Pension
How the US–UK totalization agreement prevents double contributions and combines work records, the treaty rule taxing US Social Security paid to UK residents only in the UK, and the repeal of the Windfall Elimination Provision.
Learn moreEstates & inheritance
UK inheritance tax on the long-term residence basis from April 2025 against the much larger US estate tax exemption, the 1978 estate and gift tax treaty, transatlantic gifting traps including non-citizen spouses, and why wills need both systems.
Learn moreEmployment & RSUs
How cross-border pay is taxed: sourcing salary and equity by workdays, RSUs taxed at different times and values by each country, the credit mismatches that follow, tax equalisation for assignees, and social security coordination.
Learn moreCross-border planning
Why US–UK tax planning is about timing around life events — marriage to a non-US spouse, children, a home purchase, starting a business, retirement, inheritance — and why the best options tend to close on the day the event happens.
Learn moreTalk to a US–UK tax specialist
Tell us about your situation and we’ll explain your position across both systems — what you need to file, what you can plan around, and what it will cost.
Or call +44 20 8064 3580 — we’ll tell you honestly whether you need help.