Filing UK Tax Returns as a Non-Resident Expat

A common misconception among UK expats is that leaving the country ends their relationship with HMRC. For those without any remaining UK-source income or gains, this may eventually be true. For the majority of British expats — who retain UK rental property, hold UK investments, receive a UK pension, or sold UK assets during the year — the obligation to file UK self-assessment tax returns continues indefinitely, regardless of where in the world they live.

Understanding what needs to be filed, in what format, by when, and with what consequences for non-compliance is essential financial housekeeping for any British national living abroad.

Who Must File a UK Self-Assessment Return as a Non-Resident

HMRC requires a self-assessment return from non-UK residents in the following situations:

UK rental income. This is the most common trigger for expat self-assessment. If you receive rent from UK property while living abroad, you have UK-source income that must be reported. This applies regardless of whether tax is withheld at source under the Non-Resident Landlord Scheme (see below), and regardless of the amount.

UK employment income. Income from a UK-based employer for work performed in the UK is taxable in the UK regardless of your residence status. Work performed wholly outside the UK for a UK employer may not be taxable in the UK depending on the double taxation agreement with your country of residence.

UK capital gains. Since April 2015, non-UK residents who dispose of UK residential property must report the gain to HMRC and may be liable to UK capital gains tax (Non-Resident Capital Gains Tax — NRCGT). Since April 2019, this was extended to commercial property and UK property-rich entities. The disposal must be reported within 60 days of completion, regardless of whether a tax return is also required for the year.

UK pension income. The State Pension, occupational pensions and drawdown income from UK-registered pension schemes are all potentially UK-source income. Under most double taxation agreements, private (non-government) pension income is taxed in the country of residence rather than the UK. Government Service pensions (teachers, NHS, civil service, military) are typically taxed in the UK regardless of where the recipient lives. Clarify which applies to your specific pension under the relevant DTA.

Other UK income. Savings interest from UK bank accounts, dividends from UK companies, and trust income with UK sources can all create self-assessment filing obligations for non-residents.

Significant total UK income. If your total UK-source income exceeds the personal allowance (£12,570 in 2026/27, frozen at this level — note that non-residents may not be entitled to the UK personal allowance depending on their country of residence and DTA position), a return is required. Some non-residents from EEA countries and those with appropriate DTA provisions retain entitlement to the personal allowance; others do not.

The SA100 and the SA109 Non-Resident Supplement

The UK self-assessment return for individuals is the SA100. For non-UK residents, this must be accompanied by the SA109 supplement — the Residence, remittance basis, etc. pages.

The SA109 is where you declare your residence status for the year, set out the statutory residence test (SRT) analysis confirming non-UK residence, and claim any relevant reliefs (split year treatment, personal allowance under a DTA, exemptions for foreign income). Filing the SA100 without the SA109 as a non-resident is effectively filing incorrectly — it omits the essential information about your residency position.

The SA109 cannot be filed using HMRC's basic free online filing tool (HMRC's own free service). You need either commercial tax return software (TaxCalc, GoSimpleTax, Digita, and others all support SA109) or a UK-registered tax adviser who files on your behalf.

For most non-resident expats with UK rental income and any complexity in their affairs, engaging a UK accountant or specialist expatriate tax adviser is significantly more cost-effective than the risk and stress of managing this yourself. Fees for expat self-assessment preparation range from approximately £200–600 for straightforward returns; more complex affairs with UK rental properties, capital gains and overseas income interaction cost more.

Filing Deadlines

The UK self-assessment deadlines are the same for non-residents as for UK residents:

• 31 October — paper tax return deadline for the preceding tax year (5 April year end)
• 31 January — online tax return deadline for the preceding tax year (the more practical option)
• 31 January — payment deadline for any tax due for the preceding year, plus first payment on account for the current year (if applicable)
• 31 July — second payment on account

For example, the self-assessment return for the tax year 6 April 2025 to 5 April 2026 must be filed by 31 January 2027 online, with any tax balance due paid by the same date.

Online filing from abroad is straightforward — HMRC's online portal and commercial software both permit filing from overseas. The commercial software route (required for SA109 filers as noted above) works from any country.

Penalties for Late Filing

HMRC's penalty regime for late self-assessment filing is automatic and applies regardless of whether any tax is actually owed:

• £100 fixed penalty applies immediately from day one of late filing (after 31 January for online returns)
• Daily penalties of £10 apply from three months after the deadline (from 1 May for online returns) up to a maximum of £900
• Further fixed penalties of 5% of the tax due (minimum £300) apply at six and twelve months after the deadline

For returns that are filed very late (years overdue), penalties accumulate significantly. HMRC has shown limited appetite for waiving these penalties except in cases of genuine inability to file due to circumstances outside the taxpayer's control.

If you have not filed UK returns for prior years despite having filing obligations, the best course of action is to disclose and regularise proactively, ideally through a tax adviser who can manage the process with HMRC. Voluntary disclosure before HMRC detection typically results in penalty mitigation.

HMRC Non-Resident Status Confirmation: NR1 Form

Banks — both UK and overseas — sometimes require confirmation of non-resident status for the purposes of paying interest gross (without UK income tax withholding), or for other administrative purposes. HMRC's form NR1 (or, for individuals, the process via the HMRC R105 or coding notice system) can be used to confirm non-resident status and arrange for income to be paid gross.

UK bank accounts held by non-residents can, in principle, receive interest without HMRC withholding — the non-resident must request this and confirm their non-resident status. Some banks handle this routinely; others require prompting.

Dual Filing Obligations: UK and Country of Residence

Most expats face filing obligations in two jurisdictions simultaneously: the UK (for UK-source income and gains) and their country of residence (for worldwide income in most jurisdictions).

Double taxation agreements (DTAs) exist between the UK and most countries where British expats live. These agreements determine which country has the primary right to tax different categories of income and gains, and provide mechanisms for relief from double taxation. The DTA does not, however, eliminate double filing obligations — you must typically file in both countries and then claim the relief in whichever country has the secondary right to tax.

For example, an expat in Spain receiving UK rental income will: report the rental income in Spain (worldwide income taxable there for Spanish residents) and claim deduction for any UK tax paid; and file a UK self-assessment return reporting the UK rental income and paying UK tax, which is then credited against the Spanish tax liability. The same income is not taxed twice, but it must be reported twice.

The interaction of two sets of tax rules, allowances, timing differences and currency conversions makes dual-filing genuinely complex. Most expats with both UK and overseas income benefit significantly from having advisers in both jurisdictions who communicate with each other.

Non-Resident Landlord Scheme: Withholding vs Self-Report

As noted in the renting abroad guide, the NRLS requires UK lettings agents and tenants paying rent directly to a non-resident landlord to withhold 20% of the gross rent and pay it to HMRC quarterly. This withholding is an advance payment of income tax, not a final settlement — the actual liability is determined through self-assessment and refund or additional payment follows accordingly.

Non-resident landlords can apply to receive rent gross (without withholding) by registering with HMRC's Non-Resident Landlord Scheme and demonstrating that their UK tax affairs are in order. The NRL1 form is the individual application; once approved, the letting agent is notified by HMRC and stops withholding. Approval significantly improves cash flow and avoids the need to recover withheld amounts through the refund process.

How Global Investments Can Help

Global Investments works with a network of specialist expatriate tax advisers who handle UK self-assessment for non-resident clients across all major expat destinations. We can provide introductions to advisers who understand both the UK tax position and the relevant country-of-residence tax framework — critical for ensuring DTA claims are made correctly in both jurisdictions.

For clients who have not filed UK returns for prior years and are concerned about their position, we can facilitate introductions to advisers who specialise in regularisation of historic non-compliance. The sooner this is addressed, the smaller the penalty exposure.

This article provides general information only and does not constitute tax advice. UK tax rules change annually. Always take advice from a qualified, regulated UK tax adviser for your specific circumstances.