US-UK Tax Specialist Remote Workers 2026 Guide | US-UK Tax

Introduction

You took a US-based marketing role in 2022, then moved to London in mid-2024 with your UK partner, kept the US employer on the basis that "remote is remote", and have been working from a Hackney flat for the past nineteen months while continuing to receive a US payroll cheque with US federal and California state tax withheld. You file Form 1040 each year through the US-based payroll provider's tax assistance benefit. You have not filed anything with HMRC. Your US employer believes you are working from California; your UK partner's accountant has mentioned UK tax exposure, but you have not acted. The US-UK tax specialist remote workers framework covers exactly this position — and the longer the unresolved status persists, the more complex and expensive the eventual cleanup becomes.

This guide is written for US citizens working remotely from the UK for US employers, UK citizens working remotely from the US for UK employers, US-UK dual citizens splitting time between both jurisdictions, freelance and contractor cross-border remote workers, and digital nomads cycling through extended stays in the UK and the US. By the end, you will know exactly how the residency tests operate, where treaty positioning applies, and how the integrated annual workflow works. For our broader cross-border service overview, see our US-UK cross-border tax advisory service.

What Is a US-UK Tax Specialist for Remote Workers (Definition Section)

A US UK tax specialist remote workers adviser is a cross-border tax practitioner specialising in the integrated US and UK tax position of remote workers operating across both jurisdictions — typically holding UK Chartered Tax Adviser (CTA) credentials through the Chartered Institute of Taxation at https://www.tax.org.uk plus US IRS Enrolled Agent credentials through the IRS at https://www.irs.gov/tax-professionals/enrolled-agents, with hands-on experience handling cross-border payroll, treaty positioning under Article 14 of the US-UK Income Tax Convention, UK Statutory Residence Test (Schedule 45 FA 2013) analysis, US substantial presence test under IRC Section 7701(b), Certificate of Coverage under the 1984 US-UK Totalization Agreement, FBAR via FinCEN Form 114, Form 8938 FATCA, and integrated Form 1040 plus UK Self Assessment work.

The remote worker market within cross-border tax has grown materially since 2020, driven by widespread employer adoption of distributed working models, increased US-citizen relocation to the UK on personal grounds while retaining US payroll employment, and post-Brexit cross-border employment arrangements requiring specialist handling. The HMRC remote worker guidance is available at https://www.gov.uk/hmrc-internal-manuals/employment-income-manual.

This matters specifically in 2026 because the post-April 2025 UK Foreign Income and Gains (FIG) regime under FA 2025 provides UK arrivers within their 10-year UK non-residence lookback period a 4-year UK exemption on foreign income and gains, materially changing the analysis for US-payroll remote workers in their first four UK years; because UK Statutory Residence Test enforcement has increased post-Brexit with HMRC tightening physical presence documentation requirements; and because the IRS Voluntary Disclosure Practice (VDP) under Form 14457 and the IRS Streamlined Foreign Offshore Procedures remain available as catch-up routes for remote workers who have accumulated multi-year UK tax exposure without HMRC registration.

Why a US-UK Tax Specialist for Remote Workers Matters More Than Ever in 2026

Three reasons make the US-UK tax specialist's position for workers and the remote workers' position particularly important in the 2025-26 tax year. First, the post-April 2025 UK Foreign Income and Gains (FIG) regime under FA 2025 replaced the long-standing remittance basis with a 4-year UK exemption on foreign income and gains for qualifying UK arrivals, available to individuals within their 10-year UK non-residence lookback period. US payroll remote workers moving to the UK can take their full US salary, UK tax-free, during the 4-year FIG window, with US tax continuing to apply under the Article 1(4) Saving Clause. This is materially better than the pre-April 2025 remittance basis framework for many remote workers and creates a 4-year planning window that did not previously exist.

Second, the UK Statutory Residence Test under Schedule 45 FA 2013 enforcement has tightened post-Brexit, with HMRC increasingly scrutinizing physical presence documentation, including bank account transaction location data, mobile phone location data, social media check-in data, and immigration entry-exit records cross-referenced through the UK Home Office advance passenger information feeds. Our UK Statutory Residence Test guide for cross-border workers covers the specific tests and documentation requirements. According to ONS data, approximately 4.6 million working-age UK residents performed at least some remote working in the 2024 calendar year, with a meaningful cross-border subset triggering specialist coordination needs.

Third, the IRS Voluntary Disclosure Practice and IRS Streamlined Foreign Offshore Procedures remain available throughout 2026 as the principal catch-up routes for cross-border remote workers who have accumulated multi-year UK tax exposure without HMRC registration. Streamlined Procedures require three years of amended Form 1040, six years of FBAR, and a Form 14653 non-willfulness narrative, with zero federal penalties for eligible non-willful filers, compared to the alternative penalty exposure typically running to £40,000 to £120,000 for multi-year remote worker positions. The IRS Streamlined Procedures reference sits at https://www.irs.gov/individuals/international-taxpayers/u-s-taxpayers-residing-outside-the-united-states.

How a US-UK Tax Specialist for Remote Workers Operates Across Common Scenarios

Scenario A: US citizen working remotely from the UK for a US employer

A US citizen physically working from the UK for a US-based employer faces multiple overlapping rules. The UK Statutory Residence Test under Schedule 45 FA 2013 typically establishes UK tax residence quickly — 183 days of UK physical presence in a UK tax year is automatic UK residence, with 91 days plus other UK ties (UK family, UK accommodation, UK work, prior UK residence) producing residence at lower thresholds. UK tax residence triggers UK income tax under ITEPA 2003 on the worldwide salary regardless of where the payroll is run, with HMRC PAYE registration required for the US employer if economic employer principles apply, or UK Self Assessment required from the worker if not.

The US side continues to tax the worker on worldwide income as a US citizen under IRC Section 1, with the Saving Clause under Article 1(4) of the US-UK Income Tax Convention preserving US taxing rights regardless of UK residence. Article 14 (Income from Employment) and Article 15 (Directors' Fees) typically allow the source state where the work is physically performed (the UK) to exercise primary taxing rights, with Form 1116 Foreign Tax Credit on the US side relieving US tax through the general category of UK tax paid. Roth IRA contribution eligibility requires Form 1116 FTC rather than Form 2555 FEIE positioning. IRS Publication 5, covering US citizens abroad, is available at https://www.irs.gov/publications/p54.

Scenario B: UK citizen working remotely from the US for a UK employer

A UK citizen physically working from the US for a UK-based employer faces the reverse position. The US substantial presence test under IRC Section 7701(b) typically establishes US tax residence quickly — 183 days using the 3-year weighted-average formula (current-year days plus 1/3 of prior-year days plus 1/6 of year-before-prior-year days). US tax residence triggers US federal income tax on worldwide income, plus US state income tax for state-resident workers (California, New York, Massachusetts, and other income-tax states), plus US FICA payroll tax obligation through the US-resident employer or US self-employment tax under IRC Section 1402 if self-employed.

The UK side may continue to tax the worker under the split-year residence treatment in the year of departure, under Schedule 45 FA 2013, Cases 1-3. It may continue under UK non-resident status with UK-source income exposure on UK earnings deemed UK-source under the specific provisions of ITEPA 2003. Article 14 of the US-UK Income Tax Convention typically allocates primary taxing rights to the US as the country of physical employment, with UK Self Assessment producing Foreign Tax Credit relief on the UK side against US federal tax already paid.

Scenario C: US-UK dual citizens splitting time between both jurisdictions

US-UK dual citizens splitting time between the UK and the US face the most complex position. Both countries claim taxing rights on worldwide income under domestic law — the UK under residence rules and the US under citizenship rules. The Statutory Residence Test outcome combined with the US substantial presence test produces dual residence in many cases, with Article 4 of the US-UK Income Tax Convention tiebreaker rules (permanent home, center of vital interests, habitual abode, nationality) resolving treaty residence for purposes of other treaty articles. Article 1(4) of the Saving Clause preserves US taxing rights over US citizens regardless of the treaty residence outcome.

Step-by-Step: How US UK Tax Specialist Engagement Works for Remote Workers

The first step is determining the residence status. The specialist documents the worker's physical presence in both the UK and US across the relevant tax years (UK tax years 6 April to 5 April; US tax years 1 January to 31 December), applies the UK Statutory Residence Test under Schedule 45 FA 2013 to determine UK tax residence, applies the US substantial presence test under IRC Section 7701(b) for non-US-citizens or confirms US-citizen worldwide taxation, and identifies whether the worker is UK resident only, US resident only, or dual resident in any given year. The HMRC Statutory Residence Test guidance sits at https://www.gov.uk/government/publications/rdr3-statutory-residence-test-srt.

The second step is the treaty positioning analysis under the US-UK Income Tax Convention. Article 14 (Income from Employment) typically allocates primary taxing rights to the country where the work is physically performed. Article 1(4) of the Treaty preserves US taxing rights over US citizens. Article 24 Double Taxation Relief provides the credit relief mechanism. Article 17 (Pensions) covers any retained pension positions. Article 4: Residence tiebreaker applies in dual-residence cases. Form 8833 disclosure may be required on US Form 1040 for any treaty positions taken.

The third step is the cross-border payroll analysis. For US-citizen workers physically working from the UK on US payroll, the specialist evaluates whether the US employer has an obligation to operate UK PAYE under economic employer principles, whether the worker should remain on US payroll with UK Self Assessment filing of the salary as foreign employment income, or whether the worker should transition to UK payroll through an Employer of Record (EOR) or UK Limited company structure. The HMRC EOR guidance sits at https://www.gov.uk/hmrc-internal-manuals/employment-income-manual.

The fourth step is the social security coordination under the 1984 US-UK Totalization Agreement. Cross-border remote workers should evaluate whether a Certificate of Coverage (USA/GB from the US Social Security Administration or CN-US/UK from HMRC) is required to avoid double payroll tax exposure under FICA and UK National Insurance. The SSA Certificate of Coverage application sits at https://www.ssa.gov/international/CoC-app.html.

The fifth step is the FIG regime analysis for UK arrivers. Under the post-April 2025 UK Foreign Income and Gains (FIG) regime under FA 2025, qualifying UK arrivers within their 10-year UK non-residence lookback period can elect a 4-year UK exemption on foreign income and gains. US payroll remote workers moving to the UK can typically take their US salary into the UK tax-free during the 4-year FIG window, producing material annual UK tax savings compared to the standard UK tax-resident treatment.

The sixth step is the integrated annual filing. Form 1040 with Form 1116 Foreign Tax Credit (or Form 2555 FEIE where appropriate), FBAR via FinCEN BSA E-Filing if UK account thresholds are met, Form 8938 FATCA if asset thresholds are met, Form 8833 treaty disclosure where treaty positions are taken, and UK Self Assessment with foreign employment income disclosure all run alongside under an integrated specialist workflow.

The seventh step is the ongoing annual maintenance and planning. Cross-border remote workers should review their position annually with the specialist, covering the next year's anticipated travel pattern, the FIG regime timing window for UK arrivers, Certificate of Coverage renewal (where applicable), and overall structure optimization as personal circumstances and employer arrangements evolve.

Real-World Example — US UK Tax Specialist Remote Workers in Practice

Case Study: A US Marketing Manager Working Remotely From London for a Boston Employer

Rachel is a US citizen, aged 33, working as a marketing manager at a Boston-based fintech firm, earning a $145,000 annual salary plus an annual bonus of approximately $25,000. She moved from Boston to London in mid-2024 with her UK partner, Mark (a UK citizen working in financial services), and has been working in person from a Hackney flat since arrival, remaining on the Boston-based US employer payroll with US federal income tax and Massachusetts state income tax withheld. The US employer believed Rachel had relocated to a US-based remote working address (she had given her parents' Boston suburb address for HR records) and had not adjusted payroll. Rachel had filed US Form 1040 for the 2024 tax year through her US-based payroll provider's tax assistance benefit, claiming the standard US-resident filing position with Massachusetts state tax included. She had not filed anything with HMRC.

In early 2026, Rachel engaged a US-UK Tax after Mark's accountant casually mentioned the cross-border issue. The review identified the position.

UK residence analysis under Schedule 45 FA 2013: Rachel had been physically present in the UK for approximately 220 days during the 2024-25 UK tax year (mid-2024 arrival through 5 April 2025) and was on track for approximately 340 days during the 2025-26 UK tax year. The automatic UK residence test was met (183 days of UK presence in 2024-25; substantially more in 2025-26). Rachel was a UK tax resident under Schedule 45 FA 2013 for both the 2024-25 and 2025-26 UK tax years.

Post-April 2025 FIG regime eligibility: Rachel met the 10-year UK non-residence lookback test (she had not been UK tax resident in any of the 10 UK tax years preceding her 2024 arrival). She was eligible for the 4-year UK exemption on foreign income and gains under FA 2025 from the 2025-26 UK tax year onwards. The 2024-25 UK tax year preceded the effective date of the FIG regime on 6 April 2025 and required separate analysis under the previous remittance basis or the arising basis framework.

UK tax exposure analysis: For the 2024-25 UK tax year (split-year arrival case under Schedule 45 FA 2013 Case 4 - starting full-time work in the UK), Rachel's US salary earned from the date of UK arrival mid-2024 through 5 April 2025 was UK-taxable as employment income under ITEPA 2003. UK Self Assessment was required by 31 January 2026 — the deadline had passed at the date of engagement, resulting in a late filing. UK tax on approximately £64,000 of salary earned during the UK-resident split-year portion of 2024-25, at higher rates, produced a UK tax liability of approximately £ 18,500, plus a late filing penalty of £100 and interest. Foreign Tax Credit relief was available on Form 1116 for the 2024 US tax year, and US tax in Massachusetts has already been paid on the same income.

For the 2025-26 UK tax year, the FIG election under FA 2025 resulted in a UK exemption on Rachel's full US salary of approximately £140,000 (post-2025-26 conversion). The FIG election was made on the 2025-26 UK Self Assessment due by 31 January 2027. No UK tax was due on her US salary for the 2025-26 UK tax year under the FIG regime.

US side analysis: Rachel's 2024 Form 1040 was filed as a US-resident standard filer, which was technically correct under IRC Section 1, which provides worldwide taxation for US citizens, regardless of UK residence (US citizens are always US-taxed on worldwide income). However, Form 1116 Foreign Tax Credit positioning was needed for 2024 to relieve the UK tax now being paid for the 2024-25 UK split-year portion, requiring a 2024 Form 1040X amendment. For 2025 Form 1040 going forward, Form 1116 FTC positioning was needed on the FIG-elected position. Though FIG obtained a UK exemption, the underlying US salary remained fully US-taxable under the Article 1(4) Saving Clause and required Form 1116 FTC relief on any other UK tax paid (UK National Insurance, where applicable, on UK-side employer arrangements).

Massachusetts state tax position: Massachusetts continued to claim Rachel as a state tax resident based on her HR-registered Boston suburb address and US payroll. Under Massachusetts residence rules, a domicile change is required to terminate Massachusetts tax residence, and evidence of intent to establish a new permanent home outside Massachusetts is required, including driver's license surrender, voter registration termination, changes in financial account addresses, and a pattern of physical absence. Massachusetts Voluntary Disclosure Program registration was needed to terminate the Massachusetts tax residence position retroactively to mid-2024.

Certificate of Coverage analysis under the 1984 US-UK Totalization Agreement: Rachel's US employer was continuing to withhold US FICA on her salary. UK National Insurance was not being deducted because Rachel was not on the UK payroll. Under Article 4 of the Totalization Agreement, Rachel's permanent move to the UK (not a temporary assignment lasting less than 5 years) should have resulted in her transitioning from US FICA to UK National Insurance. Still, the absence of UK payroll arrangements left her in an ambiguous position. The specialist coordinated a discussion with her US employer's HR and payroll team about either transitioning to UK payroll through an Employer of Record (EOR) or restructuring as a US-payrolled detached worker with Certificate USA/GB if the arrangement could be characterized as temporary.

The remediation route ran in four workstreams. The 2024-25 UK Self Assessment late filing workstream prepared and submitted the UK return for split-year arrival treatment under Schedule 45 FA 2013 Case 4, paid approximately £18,500 of UK tax, including the £100 late filing penalty and interest, and obtained an HMRC compliance reference for the registration.

The 2024 Form 1040X amendment workstream restated the 2024 US tax return, with Form 1116 Foreign Tax Credit absorbing US federal tax on the UK-resident portion of the year (approximately $8,200 in US federal tax savings via FTC), and submitted to the IRS by registered mail with a copy retained.

The 2025-26 UK Self Assessment with FIG election workstream prepared the return for full-year UK residence, claiming the 4-year UK exemption on foreign income and gains under FA 2025. The 2025-26 UK Self Assessment was prepared for submission by 31 January 2027 with zero UK tax due under the FIG election.

The Massachusetts Voluntary Disclosure Program workstream terminated Rachel's Massachusetts state tax residence retroactively to her mid-2024 UK departure date, obtained a refund of Massachusetts state tax withheld during the UK-resident period (approximately $7,800), and established a clean Massachusetts non-resident baseline going forward.

The going-forward structure decision recommended transitioning Rachel to UK payroll through an Employer of Record (EOR) arrangement with her US employer, terminating US FICA withholding, starting UK PAYE income tax and Class 1 National Insurance, and establishing a clean, ongoing baseline for both US and UK compliance.

The outcome was full IRS and HMRC compliance with the 2024-25 split-year UK Self Assessment filed and paid, 2024 Form 1040X amendment with FTC relief, 2025-26 UK Self Assessment with FIG election producing zero UK tax for the year, Massachusetts Voluntary Disclosure terminating state residence with refund of withheld state tax, and going-forward EOR structure recommendation under discussion with the US employer. Total US-UK Tax fee approximately £4,200 for the integrated multi-year cleanup plus first-year ongoing engagement, against the avoided exposure of accumulating UK Self Assessment late filing penalties, Massachusetts non-resident dispute risk, and HMRC enforcement on the unregistered UK tax position.

Common Mistakes People Make With US-UK Tax Specialist Remote Workers

The first mistake is assuming that the legal employment country wins over the physical presence country. Under both the UK Statutory Residence Test under Schedule 45 FA 2013 and the US substantial presence test under IRC Section 7701(b), physical presence is the dominant factor — where you actually sit and work usually wins the residence determination, with treaty positioning under Article 14 of the US-UK Income Tax Convention allocating primary taxing rights to the country of physical employment. Remote work arrangements that fail to register the worker's actual location produce compliance gaps that compound over time. The HMRC Statutory Residence Test guidance sits at https://www.gov.uk/government/publications/rdr3-statutory-residence-test-srt.

The second mistake is failing to account for the post-April 2025 UK Foreign Income and Gains (FIG) regime for UK arrivals. The FIG regime under FA 2025 provides qualifying UK arrivers (those within their 10-year UK non-residence lookback period) with a 4-year UK exemption from foreign income and gains, materially better than the standard UK tax-resident treatment for US payroll remote workers. UK arrivers should evaluate FIG election eligibility annually during the 4-year window.

The third mistake is failing to register for UK Self Assessment when UK tax residence is established. UK Self Assessment registration is required for UK-resident workers receiving foreign employment income, with HMRC late registration penalties under FA 2008 Schedule 41 starting at £100 plus interest on unpaid UK tax. The HMRC Self Assessment registration page sits at https://www.gov.uk/register-for-self-assessment.

The fourth mistake is treating Form 2555 Foreign Earned Income Exclusion as the default US treatment for UK-resident American workers. Form 2555 FEIE excludes earned income from US tax up to $130,000 in 2025, but excluded income does not count as earned income for IRA contribution purposes under IRC Section 219 (forfeiting Roth IRA eligibility) and does not count as earned income for refundable Additional Child Tax Credit purposes under IRC Section 24(d)(1)(B)(ii) (forfeiting up to $1,700 per child refundable ACTC). Form 1116 Foreign Tax Credit positioning typically produces better outcomes for UK higher-rate earners.

The fifth mistake is ignoring the 1984 US-UK Totalization Agreement on cross-border payroll. Cross-border remote workers may face double payroll-tax exposure (US FICA plus UK National Insurance) on the same employment income without a Certificate of Coverage under the Totalization Agreement. A Certificate of Coverage USA/GB from the US Social Security Administration applies to US-employer assignments to the UK of less than 5 years; a Certificate CN-US/UK from HMRC applies to UK-employer assignments to the US.

The sixth mistake is failing to terminate US state tax residency upon a permanent relocation to the UK. US state tax residence (Massachusetts, California, New York, Virginia, and other income-tax states) continues until affirmative steps are taken to establish a new domicile outside the state — driver's license surrender, voter registration termination, financial account address changes, and physical absence pattern. Without termination, state tax continues to apply on worldwide income alongside UK tax and US federal tax. The IRS guidance on US state tax for expatriates sits at https://www.irs.gov/individuals/international-taxpayers/u-s-taxpayers-residing-outside-the-united-states.

How US-UK Tax Can Help You With US-UK Tax Specialist Remote Workers

US-UK Tax is a specialist cross-border tax advisory firm focused on US-UK tax for remote workers and digital nomads operating across both jurisdictions. Our team holds UK Chartered Tax Adviser (CTA) qualifications from the Chartered Institute of Taxation, as well as US IRS Enrolled Agent (EA) credentials, supporting cross-border Form 1040 and FBAR work. We coordinate with UK Statutory Residence Test analysis under Schedule 45 FA 2013, US substantial presence test under IRC Section 7701(b), treaty positioning under Articles 4, 14, 15, and 24 of the US-UK Income Tax Convention, Certificate of Coverage applications under the 1984 US-UK Totalization Agreement, post-April 2025 UK Foreign Income and Gains (FIG) regime election under FA 2025, and integrated annual workflow combining US Form 1040, FBAR via FinCEN BSA E-Filing, Form 8938 FATCA, Form 8833 treaty disclosure, and UK Self Assessment.

For cross-border remote workers we deliver UK Statutory Residence Test analysis and physical presence documentation, US substantial presence test analysis where non-US-citizen, treaty positioning under Article 14 of the US-UK Income Tax Convention with Form 8833 disclosure where applicable, post-April 2025 FIG regime election for qualifying UK arrivers, US Form 1040 preparation with Form 1116 Foreign Tax Credit positioning preserving Roth IRA contribution eligibility, FBAR via FinCEN BSA E-Filing on UK accounts, Form 8938 FATCA where thresholds met, UK Self Assessment with foreign employment income disclosure, Certificate of Coverage application under the 1984 US-UK Totalization Agreement, US state tax termination support including Massachusetts, California, and New York Voluntary Disclosure Programs, IRS Streamlined Foreign Offshore Procedures for catch-up of missed prior years, and Employer of Record (EOR) structure coordination with cross-border employers. You can read our broader guidance on our Statutory Residence Test guide for cross-border workers.

Get in touch with our team today at or visit https://www.us-uktax.com/services/ to discuss your cross-border remote work situation.

Conclusion

Three takeaways matter most for cross-border remote workers considering a US-UK tax specialist for remote worker engagement in 2026. First, physical presence usually wins the taxing rights determination — under the UK Statutory Residence Test under Schedule 45 FA 2013 and the US substantial presence test under IRC Section 7701(b), the country where you actually sit and work typically establishes primary taxing rights through Article 14 of the US-UK Income Tax Convention, regardless of where the employer payroll is run or where the worker is HR-registered. Remote work arrangements that fail to register the actual work location produce compliance gaps that compound over time. Second, the post-April 2025 UK Foreign Income and Gains (FIG) regime under FA 2025 provides qualifying UK arrivers (those within their 10-year UK non-residence lookback period) a 4-year UK exemption on foreign income and gains, materially better than the standard UK tax-resident treatment for US-payroll remote workers — the 4-year window should be elected annually on UK Self Assessment for each eligible year, with planning to maximise the exemption value during the window. Third, integrated specialist engagement combining UK Statutory Residence Test analysis, US substantial presence test, treaty positioning under Article 14, FIG regime election, Form 1040 with Form 1116 Foreign Tax Credit, FBAR, Form 8938 FATCA, and UK Self Assessment under a single annual workflow produces materially better outcomes than fragmented US-based generalist plus UK-based generalist arrangements — the same financial data feeds every filing without coordination friction. Speak to a US-UK Tax adviser today by emailing or visiting https://www.us-uktax.com/services/.

Frequently Asked Questions About US-UK Tax Specialist Remote Workers

Q: I am a US citizen working remotely from London for a US employer — do I owe UK tax?

A: Yes, if you are a UK tax resident under the Statutory Residence Test. The UK Statutory Residence Test under Schedule 45 FA 2013 typically establishes UK tax residence quickly for remote workers physically present in the UK — 183 days of UK presence in a UK tax year is automatic UK residence, with 91 days plus other UK ties producing residence at lower thresholds. UK tax residence triggers UK income tax on worldwide salary regardless of where the payroll is run, with Article 14 of the US-UK Income Tax Convention typically allocating primary taxing rights to the UK as the country of physical employment. Form 1116, the Foreign Tax Credit, relieves US federal tax on the US Form 1040 side. The post-April 2025 UK Foreign Income and Gains (FIG) regime may produce a 4-year UK exemption if you are within your 10-year UK non-residence lookback period.

Q: How long can I work in the UK from a US employer before triggering UK tax residence?

A: Around 90 days typically, depending on other UK ties under the Statutory Residence Test. The UK Statutory Residence Test under Schedule 45 FA 2013 uses physical presence days plus a "sufficient ties" test combining UK family ties, UK accommodation ties, UK substantive work ties (40 working days or more), 90-day ties (UK presence in prior years), and country ties. For a US citizen with no prior UK residence and minimal UK family ties, approximately 120 to 180 days of UK presence typically becomes the residence threshold; for someone with a UK partner or UK accommodation, the threshold drops to approximately 90 days. The HMRC Statutory Residence Test guidance sits at https://www.gov.uk/government/publications/rdr3-statutory-residence-test-srt.

Q: Does my US employer have to register for UK PAYE if I am working remotely from the UK?

A: Possibly, under economic employer principles. The HMRC economic employer concept under the OECD Commentary on Article 15 (now Article 14 in the post-2017 model) provides that the entity that bears the cost and risk of the worker's economic activity is the relevant employer for treaty purposes, regardless of the legal employment relationship. Where a US employer benefits economically from a worker physically performing services from the UK for an extended period, a UK PAYE obligation may attach to the US employer. Most US employers without a UK presence prefer Employer of Record (EOR) structures or direct UK Limited company arrangements to avoid the UK PAYE registration. The HMRC PAYE for non-UK employers guidance sits at https://www.gov.uk/hmrc-internal-manuals/employment-procedures.

Q: What is the FIG regime, and can I use it as a US-payroll remote worker?

A: A 4-year UK exemption on foreign income and gains for qualifying UK arrivals under the post-April 2025 Foreign Income and Gains regime. The FIG regime under FA 2025 replaced the long-standing remittance basis with a straightforward 4-year UK exemption on foreign income and gains, available to qualifying UK arrivals within their 10-year UK non-residence lookback period (individuals who have not been UK tax resident in any of the 10 UK tax years preceding their arrival). US citizens moving to the UK on a US-employer payroll can typically elect FIG annually on UK Self Assessment, producing a UK exemption on their US salary for the 4-year window. The HMRC FIG guidance is part of the broader Statutory Residence Test framework at https://www.gov.uk/government/publications/rdr3-statutory-residence-test-srt.

Q: Do I have to pay both US Social Security and UK National Insurance as a remote worker?

A: Not under the 1984 US-UK Totalization Agreement. The 1984 US-UK Agreement on Social Security under 42 USC Section 433 prevents double payroll tax exposure by allocating coverage to a single system at a time. US-citizen remote workers physically performing employment in the UK permanently are typically covered by UK National Insurance and exempt from US FICA. US-citizen remote workers on US-employer assignments to the UK of less than five years can apply for a Certificate of Coverage (USA/GB) from the US Social Security Administration at https://www.ssa.gov/international/CoC-app.html to continue US FICA and remain exempt from UK National Insurance during the certified period.

Q: How do I terminate my Massachusetts state tax residence when I move to London?

A: Through affirmative steps establishing a new domicile outside Massachusetts, plus Massachusetts Voluntary Disclosure Program registration if needed for retroactive termination. Massachusetts state tax residence continues under domicile rules until affirmative steps are taken to establish a new permanent home outside the state — Massachusetts driver's license surrender, voter registration termination, financial account address changes to the new UK address, physical absence pattern from Massachusetts, and replacement of Massachusetts community ties (clubs, professional organizations, healthcare providers). The Massachusetts Department of Revenue Voluntary Disclosure Program registration process handles retroactive terminations for cases in which state tax was incorrectly withheld after departure.

Q: I am a UK citizen working remotely from New York for a UK employer — how am I taxed?

A: Primarily by the US under Article 14 of the US-UK Income Tax Convention. The US substantial presence test under IRC Section 7701(b) establishes US tax residence quickly for physical presence in the US — 183 days using the 3-year weighted formula, which triggers US worldwide income taxation regardless of UK citizenship or UK employer. Article 14 of the US-UK Income Tax Convention typically allocates primary taxing rights to the US as the country of physical employment. UK Self Assessment may continue to apply during the split-year departure year under Schedule 45 FA 2013 Cases 1-3, with UK non-residence on UK-source income only thereafter. US FICA withholding applies through the worker's US-resident employer or US self-employment tax under IRC Section 1402 if self-employed.

Q: Can US-UK Tax handle integrated annual compliance for cross-border remote workers?

A: Yes. Our standard cross-border remote worker engagement covers UK Statutory Residence Test analysis under Schedule 45 FA 2013 with physical presence documentation, US substantial presence test analysis under IRC Section 7701(b) where applicable, treaty positioning under Articles 4, 14, 15, and 24 of the US-UK Income Tax Convention, post-April 2025 FIG regime election for qualifying UK arrivers, US Form 1040 preparation with Form 1116 Foreign Tax Credit positioning preserving Roth IRA contribution and Child Tax Credit refundable ACTC eligibility, FBAR via FinCEN BSA E-Filing on UK accounts, Form 8938 FATCA where thresholds met, Form 8833 treaty disclosure where applicable, UK Self Assessment with foreign employment income disclosure, Certificate of Coverage application under the 1984 US-UK Totalization Agreement, US state tax termination support, IRS Streamlined Foreign Offshore Procedures catch-up for missed prior years, and Employer of Record (EOR) structure coordination. Fixed annual engagement fees typically range from £1,400 to £4,200 depending on complexity. Contact to discuss your cross-border remote work tax position.