UK Expat Tax Planning: Leaving the UK, the Statutory Residence Test and What to Do Before You Go

Leaving the UK is one of the most significant financial decisions an individual can make — and one of the least well-planned. The assumption that moving abroad automatically removes UK tax liability is a common and potentially expensive error. UK tax law is extensive, extraterritorial in certain respects, and specifically designed to catch those who leave without clean breaks.

This guide covers the core framework: the Statutory Residence Test (SRT), how to break UK residency properly, what income remains taxable in the UK even after leaving, and the key steps to take before departure.

Why UK Tax Residency Matters

The UK taxes residents on their worldwide income and gains. Once you are not UK-resident, UK tax generally applies only to UK-source income and gains. The difference can be enormous — particularly for individuals with large investment portfolios, significant employment income, or substantial capital gains.

The UK also has rules (particularly around domicile and the non-dom regime, now significantly reformed from April 2025) that affected the taxation of foreign-source income for long-term UK residents. The post-2025 regime has replaced the remittance basis with a four-year foreign income and gains (FIG) exemption for new residents. These changes do not affect the expatriate scenario directly, but they affect those returning to the UK and those who previously relied on the remittance basis.

The Statutory Residence Test (SRT)

The SRT, introduced in 2013, provides the framework for determining whether an individual is UK-resident in any given tax year (6 April–5 April). It involves three tests assessed in a specific sequence:

Automatic Overseas Test (AOT): if you meet any of these conditions, you are not UK-resident for that year:

• You were resident in neither of the two preceding tax years and spend fewer than 46 days in the UK.
• You were resident in one or both of the two preceding years and spend fewer than 16 days in the UK.
• You work full-time overseas (broadly 35+ hours/week on average) and spend fewer than 91 days in the UK, with fewer than 31 days of UK work.

Automatic UK Test (AUT): if you meet any of these conditions, you are UK-resident:

• You spend 183 or more days in the UK.
• Your only home is in the UK.
• You work full-time in the UK for 365 days.

Sufficient Ties Test: if neither the AOT nor AUT conclusively determines your status, the SRT looks at UK ties (family tie, accommodation tie, work tie, 90-day tie, country tie) and the number of days spent in the UK. The more ties you have, the fewer days trigger UK residency.

Key practical implication: if you leave the UK and spend more than 45 days in the UK in the first year of departure, and have not been non-resident in recent years, you are likely still UK-resident for that year. Day counting is literal — a day where you are in the UK at midnight counts (with exceptions for transit and exceptional circumstances).

The Split Year Treatment

Where an individual becomes or ceases to be UK-resident during a tax year, the SRT includes split year provisions that treat the relevant part of the year as UK-resident and the remainder as overseas. This means you are taxed as a UK resident only for the UK-resident portion of the year of departure.

There are specific split-year cases (there are eight in total); the applicable case depends on your circumstances — whether you left to work overseas, whether your partner left to work overseas, whether you ceased to have a UK home, etc. The relevant case determines the split date. Getting this right in the year of departure has material implications for the taxation of gains, dividends, and income arising around the time of departure.

What Remains UK-Taxable After You Leave

Even as a non-resident, several categories of UK-source income remain subject to UK tax:

• UK property income: rental income from UK residential or commercial property is taxable in the UK under the Non-Resident Landlord (NRL) scheme. Tenants or letting agents are required to withhold basic rate tax (20%) unless you register with HMRC for gross payment. A UK self-assessment return must still be filed.
• UK employment income: income from UK duties performed in the UK is taxable in the UK for non-residents.
• UK dividends: since 2017, UK non-residents generally do not have a UK tax liability on UK dividends beyond the dividend withholding mechanism — but the position depends on treaty provisions and specific circumstances.
• UK interest: generally exempt from UK tax for non-residents under HMRC's rules, subject to treaty provisions.
• UK pension income: most UK pension income (state pension, occupational pension, annuities) remains subject to UK income tax for non-residents — though the rate depends on the applicable double tax treaty with your country of residence.
• UK capital gains on UK residential property: non-residents have been required to report and pay CGT on disposals of UK residential property since April 2015 (and all UK property since April 2019). The 60-day reporting and payment obligation applies regardless of residency.

Capital Gains: Leaving and Returning

Departure: For individuals who leave the UK and are non-resident, most capital gains arising while overseas are outside the scope of UK CGT — with the exception of UK property. However: the "temporary non-residence" rules mean that gains on non-UK property assets disposed of during a period of temporary non-residence (broadly, where the non-resident period is five years or fewer) are brought back into UK tax charge on return. If you plan to be abroad for fewer than five complete tax years, realising large capital gains during that period may not produce the tax saving you expect unless you remain non-resident for the full five years.

Planning implication: if you have large unrealised gains on investment portfolios, shares, or other assets (not UK property), the five-year non-residence rule is the framework to work within. If your plan is to establish genuine long-term non-residence, gains can be realised tax-free. If you plan to return within five years, careful timing is needed.

ISAs, Pensions and Investments

ISAs: ISA income and gains remain sheltered from UK tax even for non-residents. You cannot contribute to an ISA while non-resident, but an existing ISA continues to accumulate free of UK tax. The key risk is that your country of residence may not recognise the ISA wrapper — meaning ISA income could be taxable in your new country. This is a material consideration in countries including India, France, and others.

UK pensions: pension contributions are not tax-relieved while non-resident (with limited exceptions for those earning UK income or within the first year of non-residency under certain schemes). Pension drawdown while non-resident is taxable in the UK but may be relieved under a double tax treaty — check the specific treaty for your country of residence.

Offshore bonds: these are sometimes used as tax-efficient investment vehicles for non-residents because they can defer income and gains within the bond until a "chargeable event." The tax position on assignment and maturity for non-UK residents is complex; specialist advice is needed.

Pre-Departure Checklist

Before leaving the UK, the following steps are worth working through with a qualified UK tax adviser:

1. Establish the SRT position: calculate the number of days you will spend in the UK in the departure year and subsequent years. Confirm which split-year case applies.
2. Review capital gains position: consider whether to crystallise gains before or after departure, given the temporary non-residence rules.
3. Review property portfolio: if you own UK property that you will let while abroad, register with the Non-Resident Landlord scheme.
4. Review pension position: understand how your new country of residence treats UK pension income under the relevant treaty.
5. Review ISA and investment holdings: consider whether the country of residence will tax ISA income; plan accordingly.
6. Review employment contracts and equity: if you hold share options, restricted shares, or deferred compensation, understand the UK and overseas tax treatment on vesting and exercise as a non-resident.
7. Notify HMRC: complete HMRC form P85 (leaving the UK) to notify HMRC of your departure and claim any in-year tax refunds.
8. Consider domicile: domicile (a separate concept from residency) affects inheritance tax. UK domiciled individuals remain subject to UK inheritance tax on worldwide assets, regardless of where they live. Changing domicile is a complex, multi-year process; it does not happen automatically on leaving.

HMRC's Self-Assessment After Departure

Many UK expats believe they can simply stop filing UK self-assessment returns after leaving. This is incorrect if you have UK-source income (property, pension, employment income for UK duties). HMRC requires annual returns until any UK income ceases.

Non-Resident Capital Gains Tax (NRCGT) reporting is a separate obligation — disposals of UK residential property must be reported to HMRC within 60 days of completion, whether or not a return is otherwise required.

Professional Advice: Where to Find It

UK expat tax is a specialist area. General accountants without specific international experience often miss the nuances of the SRT, temporary non-residence rules, and treaty interactions. Seek advisers who:

• Are chartered tax advisers (CTA) or chartered accountants (ACA/CA) with international tax experience.
• Have specific knowledge of the double tax treaty between the UK and your destination country.
• Can advise on both the UK and overseas position — or work alongside an overseas adviser who can.

Major firms with dedicated international expatriate tax practices include Deloitte, KPMG, EY, PwC, and specialist expat-focused boutiques.

Compliance note: UK tax law is complex and changes regularly. The Finance Act 2025 made significant changes to the non-domicile regime; ongoing Finance Act changes may affect other provisions. This guide is informational and does not constitute tax advice. Always consult a qualified UK tax adviser before leaving the UK.

How Global Investments Can Help

Global Investments works with internationally mobile HNW individuals navigating the financial implications of leaving the UK. We can introduce you to UK expat tax specialists, help you think through the sequencing of your departure, and connect your tax planning with your broader investment and property strategies as you establish your international life. Contact our team for a confidential conversation.