Business & Corporate Tax Services – US & UK Specialists
US UK Tax Advisors helps UK companies with US operations, US businesses expanding into the UK, and SMEs with global reach. Our dual-qualified team delivers seamless IRS and HMRC compliance, covering Form 5471, GILTI, CFC rules, and UK corporation tax returns, so your business stays compliant and tax- efficient across borders.
Cross-Border Corporate Tax Advisory – IRS & HMRC Experts
Expanding across the Atlantic brings huge opportunities— but also complex tax challenges. US UK Tax Advisors helps UK companies with US operations, US businesses expanding into the UK, and globally active SMEs stay compliant while maximising efficiency.
With expertise in both IRS and HMRC compliance, we simplify reporting, prevent double taxation, and design structures that support sustainable growth. From annual filings to strategic planning, we provide solutions tailored to your business needs.
Our dual-qualified specialists understand the differences between the US and UK tax systems. From Form 5471 compliance to corporation tax returns, we deliver strategies that protect profits, reduce liabilities, and keep businesses fully compliant—whether you ’ re a startup or a multinational.
We support businesses operating between the US and UK with cross-border tax and accounting. That covers expansion structuring, transfer pricing, GILTI and Form 5471 for US owners of foreign companies, VAT and US sales tax, treaty-based withholding, and coordinated payroll and compliance across both jurisdictions.
Key Takeaways
- Expansion structure (subsidiary, branch or LLC) drives tax, withholding and reporting outcomes
- US owners of UK companies often face GILTI and Form 5471 filing obligations
- Intercompany transactions must be priced at arm's length under both IRS and HMRC rules
- UK VAT and US state sales tax are separate systems requiring separate registration and compliance
US–UK Cross-Border Tax: Key Facts
$10,000
Aggregate in foreign accounts at any point in the year triggers a mandatory FBAR (FinCEN Form 114) for US persons.
Source: IRS — FBARWorldwide
US citizens and Green Card holders must file a US return on worldwide income every year, regardless of where they live.
Source: IRS — Citizens Abroad$120,000+
The Foreign Earned Income Exclusion lets qualifying Americans abroad exclude over $120,000 of earned income (indexed annually).
Source: IRS — FEIE31 January
UK Self Assessment online returns and any tax owed are due by 31 January following the 5 April tax year end.
Source: GOV.UK — Self AssessmentOur Expertise at a Glance
Our corporate clients choose us because we provide more than just compliance—we deliver strategies that fuel growth. By combining technical tax expertise with commercial insight, we help businesses expand globally while staying tax-efficient.
- Specialists in US–UK corporate tax compliance
- Expert guidance on Form 5471, GILTI, and CFC rules
- Alignment of UK statutory accounts with US filings
- Tailored strategies for SMEs and multinationals
- Focus on double taxation relief and profit protection
As specialist US UK Tax Advisors, we don't just prepare returns—we design tax strategies that make cross-border compliance smooth, efficient, and growth-focused. Our clients trust us to handle the technical details so they can focus on what matters most: running and expanding their businesses.
Tax Solutions That Power Business Growth
Every business has unique goals, but one constant remains—tax compliance cannot be ignored. We provide complete support with corporate tax filings, cross-border reporting, and international structuring, allowing your team to stay focused on building and scaling the business. Our advisors bring expertise in IRS requirements, HMRC obligations, and the US–UK tax treaty, helping businesses navigate compliance with confidence.
From highly technical areas such as GILTI tax, Controlled Foreign Corporation (CFC) rules, and international shareholding requirements, through to crypto and digital asset reporting, we simplify even the most complex corporate tax challenges. Our role is to protect profits, reduce risks, and ensure that global operations remain tax-efficient.
Whether you operate as an LLC, LLP, or UK Ltd company, we ensure your structure works efficiently across both the IRS and HMRC. We also provide tailored, cost-effective support for freelancers and SMEs entering international markets, giving smaller businesses the same level of cross-border expertise normally reserved for multinationals.
Businesses & Corporates — US-UK Tax FAQs
What structure should a UK company use to expand into the US?
The right structure depends on your goals, funding and exit plans. Common options include a US C-corporation subsidiary, an LLC or a branch, each with different tax, liability and reporting consequences. A US subsidiary owned by a UK parent affects treaty benefits, withholding and profit repatriation. We model the alternatives before you commit so the structure supports growth and minimises overall tax.
What is GILTI and Form 5471, and when do they apply?
US shareholders who own 10% or more of a foreign corporation must generally file Form 5471 and may be subject to GILTI, which taxes certain foreign earnings currently rather than on repatriation. This commonly affects US owners of UK companies. We calculate GILTI, prepare Form 5471, and use elections and credits to manage the US tax cost.
How does transfer pricing work between US and UK group companies?
Transactions between related US and UK entities, such as management fees, intercompany loans or shared services, must be priced at arm's length under both IRS and HMRC rules. Getting this wrong risks double taxation and penalties. We help set defensible transfer pricing policies, prepare supporting documentation and align intercompany agreements with how the group actually operates.
Do we need to worry about both UK VAT and US sales tax?
Yes, they are separate systems. UK VAT is a broad consumption tax charged on most goods and services, while US sales tax is levied by individual states, often triggered by economic nexus once sales into a state pass a threshold. A business selling on both sides of the Atlantic must register and comply in each relevant jurisdiction. We map your obligations.
How are cross-border payments like dividends and royalties taxed?
Payments of dividends, interest and royalties between the US and UK can attract withholding tax, but the US-UK treaty often reduces or eliminates it where conditions and documentation (such as US Forms W-8) are met. Correct treaty positions and paperwork are essential to avoid unnecessary withholding. We structure intercompany flows and handle the required certifications.
Can you handle US and UK payroll for staff in both countries?
Yes. Employing people across both countries brings US federal and state payroll obligations alongside UK PAYE and National Insurance, plus considerations for cross-border and remote workers. Social security is coordinated by the US-UK Totalization Agreement so employees generally pay into one system. We set up compliant payroll and advise on assignments and remote-working risk.
Written & reviewed by the US-UK Tax Advisors cross-border tax team — chartered specialists in US and UK taxation, IRS and HMRC compliance, FATCA/FBAR reporting and double-taxation treaty planning.
Last reviewed: July 2026. This page is for general information and is not personal tax advice.
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Managing cross-border taxes doesn't have to be complicated. Whether you're a US citizen living in the UK, a UK resident with US tax obligations, or a business operating internationally, our team of specialist US UK tax accountants in London is here to help.