Your first UK tax return as a foreign national: the 2025/26 guide

Probably yes. GOV.UK says that if you are UK resident with foreign income or capital gains you usually need to fill in a Self Assessment return. The narrow exception is where your only foreign income is dividends, your total dividends (UK included) are under the £500 dividend allowance, and you have nothing else to report (GOV.UK).

Untaxed income such as rent, savings interest, dividends or foreign income can also require a return (GOV.UK). Income from the Channel Islands and the Isle of Man counts as foreign.

There is a second reason to file. The reliefs that protect a new arrival are not automatic. FIG relief, Overseas Workday Relief and a Temporary Repatriation Facility election are claims or elections made on the SA109 residence pages of a return, and split-year treatment must be shown there too: leave it off and HMRC taxes you as resident for the whole year. No return means no claim, and a UK resident with no claim is taxed on worldwide income. See whether you still file when FIG covers all your foreign income.

For 2025/26 you had to tell HMRC by 5 October 2026 if you needed a return and had never sent one, or had registered before but did not need to send one for 2024/25. Registering after that could lead to a penalty (GOV.UK). If that is you:

• Register now. Your filing deadline moves: HMRC sends a letter or email with a different deadline, 3 months from the date on it (GOV.UK). The 2025/26 return notes put it as 31 January 2027 or 3 months after the date on your notice, if that is later (SA150 notes, GOV.UK).
• The payment deadline does not move. The tax is still due by 11:59pm on 31 January 2027.
• Pay in full by 31 January 2027 if you can. A failure to notify penalty may arise if you register after 5 October and do not pay all of your tax bill by 31 January. It is based on the amount still unpaid (GOV.UK).
• Under HMRC factsheet CC/FS11 there is no penalty where you had a reasonable excuse, the failure was not deliberate and you told HMRC without unreasonable delay once the excuse ended. For a non-deliberate failure disclosed unprompted within 12 months of the tax being due, the range is 0% to 30% of potential lost revenue (GOV.UK).

Registration produces your Unique Taxpayer Reference (UTR), a 10-digit number. After online registration it appears in your personal tax account within 72 hours. After postal registration on form SA1 it usually arrives in 15 working days, or 21 days if you are abroad, and can take longer in busy periods (GOV.UK).

If you want an agent to file for you, you must register for Self Assessment first. The agent then gets your authority through HMRC's Online Agent Authorisation service or the 64-8 paper form (GOV.UK). You remain legally responsible for your own tax, and you must check and confirm the return before your agent submits it.

Residence comes first. The Statutory Residence Test (SRT) decides your status for each tax year as a whole, and it ignores nationality and domicile. Spending 183 or more days in the UK in the tax year makes you automatically resident. Someone who was not UK resident in any of the three previous tax years is automatically non-resident on fewer than 46 UK days. Between those points, the automatic UK tests come next, such as the home test, which can apply where your only home is in the UK and you spend at least 30 days there in the year. If none applies, the answer turns on your ties, and an arriver has four possible ties rather than five because the country tie does not apply.

Many 2025/26 arrivers are resident for the whole year but can use split-year treatment if they meet one of the arriver cases. The year divides into an overseas part, taxed broadly as non-resident, and a UK part from the split date, taxed as resident. Five arriver cases, Case 4 to Case 8, cover situations such as starting full-time work or a home in the UK. Each needs you to have been non-resident in the previous tax year, and each has its own split date. Where more than one fits, Cases 6 and 7 broadly take priority, and otherwise the case giving the earliest split date applies. You do not get to pick.

Two points catch people. The split is shown on the SA109: box 3 where split-year treatment applies and box 23 for your date of arrival. Leave it off and HMRC taxes you as resident for the whole year. And a split year does not shelter everything: UK employment earnings for UK duties and most UK property income stay taxable in both parts of the year. Test your dates with our SRT calculator and split-year tool before anything is filed.

The four-year FIG regime replaced the remittance basis on 6 April 2025, so 2025/26 was its first year and the returns due by 31 January 2027 carry the first FIG claims ever filed. You qualify as a new resident if the year is one of your first 4 years of UK residence after at least 10 consecutive tax years of non-UK residence (HS266, GOV.UK). Returning British expats can qualify too. If you became resident before 6 April 2025, a transitional rule lets you claim from 2025/26 for whatever years remain in your original window.

You put an X in SA109 box 28 for foreign income and box 29 for foreign gains, then report each relieved amount, source by source, on the supplementary pages: the SA106 for foreign investment and property income and the SA108 for foreign gains. HMRC's manual says there is no automatic relief, and that while getting a figure wrong does not invalidate a claim, not quantifying it at all does (RFIG42100, HMRC). The claim has to be made again for every year you want relief. The time limit for a 2025/26 claim is 31 January 2028, but the claim belongs in the return you file now.

Claiming has a price. A FIG claim costs your £12,570 Personal Allowance and your £3,000 CGT annual exempt amount for the year, even if you claim on income only. You cannot also claim Foreign Tax Credit Relief on income covered by the claim. UK-source income and gains, such as UK salary, UK rents and UK property gains, stay taxable as normal. In an illustration from our FIG guide, someone with £3,000 of foreign interest and a £60,000 UK salary would save at most £1,200 by claiming but lose a Personal Allowance worth roughly £5,028 against the salary. Check your dates with the FIG checker, and see how to claim the FIG regime on your first return for the box-by-box walkthrough.

A split year of arrival still supports a claim, but it counts as a full year of UK residence for the four-year window. Arrive in February 2026 and 2025/26 has still used the first of your four years (RFIG44000, HMRC).

If you have lived here longer, the rules changed. The remittance basis was abolished from 6 April 2025 and 2024/25 was the last year it could be claimed. From 2025/26 every UK resident is taxed on worldwide income and gains as they arise, unless they qualify for and claim FIG relief. Long-term non-doms resident for more than four years get no FIG relief at all. See FIG regime vs remittance basis.

Pre-6 April 2025 foreign income and gains that arose on the remittance basis are still taxable if brought to the UK. The Temporary Repatriation Facility (TRF) lets former remittance-basis users designate that money and pay a flat charge instead: 12% for 2025/26 and 2026/27, and 15% for 2027/28 (HS264, GOV.UK). The charge is on capital, not a tax on income or gains. Once designated and charged, the money can come to the UK at any time with no further UK tax, and you do not have to move it during the window.

The election is made on the SA109 of your return. On the 2025/26 form, box 50 is the TRF election, box 51 your personal designations, box 52 designations relating to trust capital payments and benefits, and box 53 the amount of designations remitted in the year. A 2025/26 designation is treated as made on 6 April 2025, which sets the sterling conversion date. There is no exemption for money used to pay the charge, so paying it from undesignated pre-2025 foreign income or gains is itself a taxable remittance. Pay from designated funds or clean capital. The facility closes after 5 April 2028.

A first return is rarely just the main form.

Convert foreign income into pounds at the exchange rate when it arose, and enter the full amount even if you never brought the money to the UK (SA106 notes, GOV.UK). Where foreign tax was paid and you are not claiming FIG on that income, Foreign Tax Credit Relief gives a UK credit of the lower of the foreign tax paid (or the amount the treaty allows) and the UK tax on that income, worked out separately for each item. HMRC calculates it if the relevant boxes are completed and the return is filed by the deadline, and you may not recover all the foreign tax. Our double tax relief guide goes further.

The SA109 sets your filing route. To submit it online you need commercial software or a professional agent; HMRC's free online service will not take it (SA109 notes, GOV.UK). A paper return must reach HMRC by 11:59pm on 31 October 2026. After that, a paper return is late, so filing online through commercial software or an agent is the only way to file on time by 31 January 2027. If you registered late, your filing deadline is the one in HMRC's letter or email. Our guide on why the SA109 cannot be filed on HMRC's website covers the options. Horizon files the SA109 as your authorised agent. Book a free 30-minute clarity call to start your 2025/26 return.

On 31 January 2027 you pay the 2025/26 balance and, where it applies, your first payment on account for 2026/27. The second payment on account is due by 31 July 2027. Each payment is half of the previous year's tax (GOV.UK). You do not make them if last year's bill was under £1,000, or if more than 80% of your tax was collected outside Self Assessment, for example through PAYE.

A first-time filer has paid nothing in advance, so January collects the whole year at once plus half again. A £20,000 liability becomes a £30,000 payment on 31 January 2027, with £10,000 more on 31 July 2027. FIG claimants are not immune: losing the Personal Allowance means UK salary, rent and gains are taxed from the first pound. Try our income tax calculator.

If you already pay tax through PAYE, as an employee or on a company pension, and owe less than £3,000, you can ask for the balance to be collected through your PAYE tax code, provided you file online by 11:59pm on 30 December 2026. You cannot make a part payment to get under the £3,000 threshold (GOV.UK). Paying from an overseas account works, using your 10-digit UTR followed by the letter K as the reference, but overseas payments can take longer, so check with your bank.

Late payment interest runs at Bank of England base rate plus 4%. Late payment penalties are 5% of the tax unpaid at 30 days, 6 months and 12 months. A late return gets an initial £100 penalty, then £10 a day after 3 months up to £900, then 5% of the tax due or £300, whichever is greater, at 6 and at 12 months (GOV.UK).

Americans file twice. The US taxes citizens and green card holders on worldwide income wherever they live, so a US Form 1040 is due every year alongside UK Self Assessment. Americans can still claim the UK FIG regime on the same residence-based terms as anyone else. The catch is that a FIG claim takes the UK tax on that income to nil, which leaves no UK tax to credit on the US return, so the income is simply taxed in the US instead.

Three more points. An ISA is tax-free in the UK only, and most UK pooled funds are PFICs with punitive US treatment, so check before you invest here. Foreign accounts totalling more than $10,000 at any point in the year need an FBAR. And the two tax years differ: the UK runs 6 April to 5 April, the US runs on the calendar year. See Americans living in the UK, US-UK arrival year planning and the PFIC and ISA traps, or try the UK-US take-home calculator.

All of this relates to the year ended 5 April 2026. Overseas institutions are slow, so ask this week.

• Your UTR, or confirmation that you have registered, plus your National Insurance number if you have one.
• Your residence history for the 10 tax years before arrival, with UK days in and out, to evidence FIG eligibility.
• Travel records for 2025/26: arrival date, UK day counts and the facts behind your split-year case.
• P60 or P45, payslips and bonus or equity statements, plus a workday calendar if you will claim OWR.
• Year-end statements for every foreign bank and brokerage account, showing interest and dividends between 6 April 2025 and 5 April 2026 in the original currency.
• Completion statements and cost history for foreign assets sold, foreign rental and pension paperwork, and evidence of foreign tax paid.
• UK bank interest, UK dividend vouchers and UK rental figures.
• For former remittance-basis users, a schedule of pre-6 April 2025 foreign income and gains still held offshore.

Horizon UK Tax Solutions prepares and files first returns for new UK residents. We are a Chartered Tax Adviser practice, founder-led by Jordan Onraet-Wells, based in London and working with clients across six continents, with everything handled remotely and direct access to the adviser. Jordan brings over 10 years of experience, including 7 at a Big Four firm. Rated 5.0 on Google (19 reviews), and AML-supervised.

We file as your authorised agent with HMRC, including the SA109 pages HMRC's free service cannot file. That covers FIG claims, Overseas Workday Relief, split-year claims, SA106 foreign income and Foreign Tax Credit Relief. For Americans we lead on the UK position and coordinate vetted US specialists; we do not file the US return ourselves.

Fees are fixed and published. A Standard Personal Tax Return is £350. A Non-Resident and Expat Tax Return is £550. A Complex Personal Tax Return, for multiple income streams, investments, trusts or complex structures, starts from £750. Which applies depends on what your return has to carry. We confirm it on the clarity call and fix the fee in writing before any work starts. Advisory and planning work is quoted as a fixed fee agreed in writing before work starts. We never bill by the hour. Try the fee estimator.

You book a free 30-minute clarity call. We send a fixed quote and engagement. We complete identity and address checks before work starts, as anti-money-laundering rules require. You upload documents to a secure client portal. We prepare the return, you review and approve it, and we file it and confirm what to pay and when. Book your free clarity call.