Resources · Calculators
Cross-border tax calculators & tools
Our free tools help Americans in the UK, Brits in the US and dual citizens understand their cross-border tax position — from whether you'll be taxed twice, to whether you need to file an FBAR, to which US relief leaves you better off. Each gives an indicative estimate, then connects you to a specialist.
US/UK Double-Tax Estimator
See whether your income is at risk of being taxed twice — and roughly how much relief the Foreign Tax Credit and treaty could provide.
Open calculatorFBAR Requirement Checker
Answer three questions to find out whether you need to file an FBAR (FinCEN 114) this year.
Open calculatorStreamlined Filing Eligibility
Check whether you may qualify for the IRS Streamlined programme to catch up penalty-free.
Open calculatorFEIE vs Foreign Tax Credit
See which relief is likely to leave you better off as an American in the UK.
Open calculatorUK Statutory Residence Test
Work through the SRT to estimate your UK tax-residence status for the year.
Open calculatorSelf Assessment Deadline & Penalty
Find your filing deadlines and estimate HMRC late penalties.
Open calculatorUS Expat Tax Deadlines
Your US filing dates as an American abroad, including the automatic extension.
Open calculator4-Year FIG Regime Checker
Check if you qualify for the Foreign Income & Gains regime that replaced the remittance basis in April 2025.
Open calculatorUK Corporation Tax Estimator
Estimate your UK company’s Corporation Tax, including marginal relief.
Open calculatorUS vs UK Take-Home Pay
Compare net pay across the two systems when considering a move.
Open calculatorUS Expat Tax Refund Estimator
Estimate whether you are owed a US federal tax refund after the Foreign Tax Credit.
Open calculatorUK PAYE Tax Refund Estimator
Estimate whether you overpaid UK income tax through PAYE.
Open calculatorUK vs US Capital Gains Tax Estimator
Compare UK CGT and US federal capital gains tax on the same disposal.
Open calculatorExit Tax / Covered Expatriate Estimator
Screen covered-expatriate status under IRC §877A before renouncing.
Open calculatorUS Late-Filing Penalty Estimator
Estimate failure-to-file and failure-to-pay penalties on a late US return, and see how catch-up routes can remove them.
Open calculatorDelinquent FBAR Penalty Estimator
See which IRS catch-up procedure applies to missed FBARs.
Open calculatorFrequently asked questions
Yes. Every tool here is free and gives an indicative estimate to help you understand your cross-border position. They are educational, not formal advice — for a precise answer we offer a £550 30-minute consultation, and general questions are answered free by email.
They use current headline rules and rates to give a directional figure. Real outcomes depend on the full detail of your situation, which is why each tool ends with the option to speak to a specialist.
Want a precise answer for your situation?
The tools give you a direction. A £550 30-minute consultation gives you certainty — and quick questions are answered free by email.