Skip to content
HorizonUK Tax Solutions

Cross-Border Business

How are UK EMI share options taxed if I am a US citizen?

Answered by Jordan Onraet-Wells, Founder & Chartered Tax Adviser (CTA). Published 17 August 2026. Last reviewed 17 August 2026.

The short answer

On the UK side, normally: EMI options carry no UK income tax or National Insurance on exercise if the exercise price was at least the market value of the shares at grant, and the conditions are met. The problem is the American side. The United States taxes its citizens on worldwide income wherever they live, EMI has no equivalent US status, and so the US applies its own rules to grant, exercise and sale on its own timing and amounts. A UK exercise with no UK income tax can still be a taxable event on the US return, with little UK tax available to credit against it, so the US position should be modelled before the option agreement is signed, not at exercise.

  • EMI allows options over shares worth up to £250,000 in a three-year period, requires at least 25 hours a week or 75% of your working time for the company, and charges no UK income tax or NIC on exercise at a market value strike price.
  • None of the UK relief travels: the US does not recognise EMI as a qualified plan, so a US citizen remains taxable under US rules regardless of the UK treatment.
  • The timing mismatch is the sting: if the UK charges no tax at exercise while the US does, there is little UK tax to credit on the US return for that event.
  • A disqualifying event, such as your role moving to an overseas group company or your working time falling below the threshold, ends the protection unless the option is exercised within 90 days.
  • On a later sale, the UK can apply Business Asset Disposal Relief at 18% without the usual 5% shareholding test, provided the option was granted at least two years before the sale.

The UK side: EMI relief still works

EMI remains the most generous UK option regime, and from 6 April 2026 it reaches much larger companies: gross assets of £120 million or less and fewer than 500 full-time employees. You pay no UK income tax or National Insurance on exercise if the exercise price was at least the market value of the shares when the option was granted, provided the option is exercised within its stated window (GOV.UK). Being a US citizen changes none of that UK analysis. What can break it is a disqualifying event, for example your role shifting to an overseas group company or your committed working time falling below 25 hours a week or 75% of your total working time: exercise within 90 days of the event and the advantages are preserved, miss it and a tax charge arises on exercise. The full cross-border picture is in our guide to share options and equity awards across borders.

The US side: no EMI equivalent, and a timing mismatch

The United States taxes its citizens on worldwide income wherever they live, and EMI has no US qualified status, so the US applies its own rules to grant, exercise and sale on its own timing and amounts. The result is that a UK exercise with no UK income tax can still be a taxable event on the US return, and because the two countries tax different amounts at different moments, there may be little UK tax to credit against the US bill for that event. UK accountants who set up EMI schemes are often excellent on the UK side and silent on this, which is exactly why the US position should be modelled before you sign the option agreement. We advise on the UK side and coordinate the US side through our US partners, Enrolled Agents and CPAs, so both filings are built from the same facts; the wider picture for Americans living in the UK and the US-UK treaty each have their own guides.

On sale: the UK sweetener, and what to do now

EMI shares carry a further UK advantage at the end: Business Asset Disposal Relief can apply without the 5% shareholding test that other shares need, provided the shares were acquired after 5 April 2013 and the option was granted at least two years before the sale, taxing qualifying gains at 18% for disposals from 6 April 2026 against the main higher CGT rate of 24% (GOV.UK). The US will run its own computation on the same sale, so the sequencing of exercise and sale deserves planning on both sides; our guide to selling shares in your company covers the UK disposal rules. Horizon UK Tax Solutions handles cross-border equity on fixed fees agreed upfront, with complex work from £750 and our US partners coordinated for you; book a free 30-minute clarity call before you sign, not after you exercise.

Go deeper

Sources and further reading

This is general information for the 2026/27 UK tax year, not personal tax advice; speak to a Chartered Tax Adviser about your own position.

Applies to you? Ask us directly

A page can only take you so far. Book a free 30-minute clarity call with Jordan, a Chartered Tax Adviser, and get this answered for your exact situation, on a fixed fee agreed upfront.

All quick answers
WhatsApp