For the returns that are anything but simple
US Tax Experts for Complex Expat Returns
US tax experts for Americans in the UK whose returns go beyond a single payslip — foreign accounts, UK pensions and funds, company ownership, equity pay and years of catch-up filing.
Once your return involves more than one W-2, the US rules get sharp: FBAR and Form 8938 thresholds, PFIC treatment of UK funds and ISAs, controlled-foreign-company reporting, treaty positions on pensions and dividends, and the currency and timing traps that generalist preparers miss. That is where US tax experts earn their fee.
TaxYork advises Americans in the UK with genuinely complex positions — founders and company owners, investors, executives with stock options, landlords, and people several years behind on filing. We prepare your US and UK returns together, apply the credits and treaty articles that lower your bill, and document the positions properly so they hold up.
Every engagement starts with a review and a fixed quote, so you know the cost and the plan before we begin.
Where our US tax experts add the most value
IRS Streamlined Filing
Years behind? Come back into compliance penalty-free through the Streamlined Foreign Offshore Procedures.
Catch up on filingFBAR & FATCA
Accurate FinCEN 114 and Form 8938 reporting across all your UK accounts and pensions.
FBAR & FATCACross-Border Planning
Elections, structure and equity timing modelled before you commit — for founders and investors.
Cross-border planningTreaty Optimisation
The US-UK treaty applied to pensions, gains, dividends and remittances.
Treaty planningUS & UK Returns
Both returns prepared together so credits and figures reconcile.
US tax returnsFree Calculators
Model your US and UK position before you get in touch.
Try the calculators
Once your return goes beyond a single payslip, the US rules get sharp. That is exactly where expertise pays for itself.
Talk to usWhen your expat return needs a US tax expert
A single US salary and nothing else rarely needs specialist help. It is the additions that do: foreign accounts over the FBAR threshold, UK pensions and ISAs, rental property, self-employment, a stake in a company, stock options or RSUs, or several missed years of filing. Each one pulls in a form or an election that general software never prompts for — and where US tax experts earn their fee.
The common thread is that a wrong answer is expensive and often invisible until the IRS or HMRC raises it years later. Getting the position right the first time, and documenting it so it holds up, is cheaper than unwinding it under enquiry.
The hard areas we handle
PFICs. UK funds, investment trusts and ISAs are almost always PFICs to the IRS, taxed under a punitive default regime unless you make a timely QEF or mark-to-market election on Form 8621. The ISA’s UK tax-free status counts for nothing on the US side.
Company ownership. A US shareholder of a UK company files Form 5471 and can face GILTI tax on undistributed profits — tax due before any money reaches you, with penalties from $10,000 for a missed form.
Equity pay. RSUs, options and share awards are taxed on different dates in each country. A UK section 431 election has just 14 days and a US section 83(b) election 30 days; miss either and the position worsens permanently.
Pensions. The US-UK treaty decides when UK pension growth and withdrawals are taxable in the US, and the 25% UK tax-free lump sum is not automatically tax-free to the IRS.
Getting back on track without the penalties
Behind on filing? Most non-wilful Americans qualify for the IRS Streamlined Foreign Offshore Procedures: three years of returns, six years of FBARs, and penalties typically waived entirely. It is the single most valuable route for expats who have simply not realised they had to file.
Where penalties have already been assessed, there are abatement routes — reasonable cause and Form 843 — that need to be evidenced properly to succeed. Experienced US tax experts know what a persuasive submission looks like and what the IRS actually accepts.
Every engagement starts with a review and a fixed quote, so you know the cost and the plan before we begin.
US tax expert vs tax software vs a generalist accountant
For a straightforward return, any of these works. For a cross-border return with foreign accounts, funds or a company, the gaps become expensive fast.
| What you get | US tax expert | Tax software | Generalist accountant |
|---|---|---|---|
| FBAR & Form 8938 done correctly | Limited | ||
| PFIC / Form 8621 on UK funds | |||
| Form 5471 & GILTI | |||
| Applies the US-UK tax treaty | Rarely | ||
| Streamlined catch-up filing | Rarely | ||
| Reviews your full situation first | Sometimes |
Why complex filers choose our US tax experts
Depth on the hard stuff
PFIC, Form 5471, GILTI, equity pay and treaty positions are everyday work, not edge cases we avoid.
Positions that hold up
We document elections and treaty claims properly, so they survive scrutiny.
US and UK together
Both returns prepared by one team, so nothing falls through the gap between two accountants.
Fixed fees
A clear price after a short review — the expertise costs far less than a wrong return.
How it works
Consultation
We map your income, accounts, entities and filing history.
Fixed quote
A clear fee and a plan for both your US and UK filings.
Preparation
Complex positions prepared and documented, credits and treaty articles applied.
File & advise
We file and set out the planning that lowers future bills.
Frequently asked questions
What makes someone a US tax expert for expats?
A US tax expert for expats knows how the US worldwide-taxation system interacts with a foreign country. For Americans in the UK that means the Foreign Tax Credit and FEIE, FBAR and FATCA reporting, PFIC rules on UK funds, the US-UK treaty, and the Streamlined catch-up programme — applied together rather than in isolation.
When should I bring in US tax experts?
When your return goes beyond a single W-2: foreign accounts over the FBAR threshold, UK pensions and ISAs, rental property, self-employment, company ownership, stock options, or several years of missed filings. These are where general software and generalist accountants make costly mistakes.
Do US tax experts also handle my UK tax?
Yes. TaxYork prepares your UK Self Assessment alongside your US return so both agree, with the Foreign Tax Credit and treaty positions applied consistently across the two systems.
Can US tax experts reduce IRS penalties?
Often, yes. For non-wilful non-compliance the Streamlined Foreign Offshore Procedures typically waive penalties entirely, and where penalties have been assessed there are abatement routes such as reasonable cause and Form 843.
Are US tax experts worth it versus tax software?
Software rarely handles FBAR, Form 8938, PFIC reporting or treaty positions correctly, and it cannot flag what you are missing. For a cross-border return the fee for an expert is usually far less than the tax, penalties or missed reliefs that a wrong DIY return costs.
How do I start with your US tax experts?
Book a short consultation. We review your situation, quote a fixed fee, and set out exactly what your US and UK filings will involve before any work begins.
Do US tax experts handle PFICs and UK funds?
Yes. UK funds, OEICs, investment trusts and ISAs are almost always PFICs to the IRS, taxed under a punitive default regime unless a timely QEF or mark-to-market election is made on Form 8621. This is one of the most common and costly things software and generalist accountants get wrong.
Can you handle stock options and RSUs across both countries?
Yes. Equity pay is taxed on different dates in the US and the UK, and the election deadlines are unforgiving — a UK section 431 election must be made within 14 days and a US section 83(b) election within 30 days. Miss either and the tax position worsens permanently, so getting the timing right is exactly where expertise pays.
Do you deal with UK company ownership?
Yes. A US shareholder of a UK company usually files Form 5471 and can face GILTI tax on their share of the company’s undistributed profits. We prepare that alongside your UK corporation tax and personal return so the two agree.
How are UK pensions taxed on my US return?
The US-UK treaty decides when UK pension growth and withdrawals are taxable in the US. Importantly, the 25% UK tax-free lump sum is not automatically tax-free to the IRS, so it needs a considered treaty position rather than an assumption that the UK treatment carries across.
Get in Touch
Ready to get
your US taxes
sorted?
Whether you need help with IRS Streamlined filings, annual US tax returns, or cross-border tax planning — our team is here for you.
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