US-UK · Journal
SA109 Residence Pages: A Guide for US Citizens in the UK
What the SA109 residence pages cover, why HMRC's own online Self Assessment service cannot file them, and which supplementary pages an American in the UK needs alongside them.
What the SA109 residence pages cover, why HMRC's own online Self Assessment service cannot file them, and which supplementary pages an American in the UK needs alongside them.
The SA109 is the supplementary page of the UK Self Assessment return on which you state your residence status. You need it if you are claiming non-residence, split-year treatment, relief under the foreign income and gains (FIG) regime, or personal allowances under a double taxation agreement. The practical trap is that HMRC's own free online service cannot file it, so a return including the residence pages must go in on paper by 31 October, or through commercial software or an agent by 31 January.
The SA100 is the main Self Assessment return, and it assumes you were an ordinary UK resident for the whole tax year. The moment that assumption breaks — you arrived mid-year, you left mid-year, you are non-resident or dual resident, or you want a relief only new arrivals can claim — HMRC needs a separate page. That page is the SA109.
GOV.UK describes it as the page used to record your residence and domicile status and to claim personal allowances as a non-UK resident. The title changed for 2025-26: the form is now "Residence and foreign income and gains (FIG) regime etc (Self Assessment SA109)", reflecting the end of the remittance basis and the arrival of the FIG regime from 6 April 2025. The previous year's version sits on the same page under its old name, and supplementary pages are filed by tax year, so a late 2024-25 return still needs the 2025 edition.
HMRC's SA109 notes for 2025-26 say to complete the pages if you are not resident in the UK, or if you are UK resident and any of the following applies:
Two of those matter disproportionately to Americans. Split-year treatment is needed by almost everyone moving in either direction, in the year of the move. The FIG regime is available only to a "qualifying new resident" — HMRC's guidance describes this as someone in one of their first four years of UK residence after at least ten consecutive tax years of non-UK residence — and the claim is made in box 28 of the SA109, not on the foreign pages, even though the income is reported there. Our explainer on the FIG regime for US citizens in the UK covers that interaction.
The SA109 is also where a non-resident or dual resident claims personal allowances under a double taxation agreement, at box 15 — the UK side of a treaty residence position. Our note on the US-UK treaty tie-breaker rules explains how that analysis works before it reaches a form.
HMRC's notes to the SA109 state that to submit the residence pages online you will need to purchase software from a commercial supplier, or authorise a professional agent to file on your behalf. They then add a specific prohibition: do not submit the residence pages as an electronic attachment to your online filed tax return. GOV.UK's filing page says the same thing from the other direction — you cannot use HMRC's online service if you lived abroad as a non-resident, and should use commercial software or download the forms instead.
A return that includes the SA109 therefore has exactly three routes:
1. Paper. Download the SA100 and every supplementary page you need, complete them, and post them so HMRC receives them by 31 October.
2. Commercial software. Buy a package from HMRC's published list of suppliers that supports the residence pages — not every package does — and file by 31 January.
3. An agent. Authorise an accountant to file for you; agents use commercial software and work to 31 January.
For most taxpayers the 31 October deadline is irrelevant, because they file online in January. For an SA109 filer it is a gate. Miss it and the paper route closes; you are then committed to buying software or engaging an agent before 31 January, whether or not you had intended to.
HMRC's deadlines for the 2025 to 2026 tax year are:
Late filing carries an initial £100 penalty, then daily penalties of £10 a day up to £900 after three months, then at six months a further 5% of the tax due or £300, whichever is greater, and the same again at twelve months. HMRC's foreign notes add a related point: if you conclude you do not need to file at all, tell HMRC by 31 January 2027.
Step by step, a clean SA109 filing season looks like this:
1. Settle the residence analysis first — resident, non-resident, or split year, and under which case. Everything follows from it.
2. Decide the filing route — paper, software or agent — in September, not late October.
3. Pull together the supplementary pages you need and reconcile them to the underlying records.
4. Complete the SA109 last; several boxes depend on dates and figures settled on the other pages.
5. Keep a dated copy of everything filed. It supports the foreign tax credit you will claim in the US.
Americans in the UK rarely file an SA100 and nothing else. These are the pages most cross-border filers use, with their current GOV.UK titles.
| Page | What it covers | You need it when |
| --- | --- | --- |
| SA102 — Self Assessment: Employment | Employment income and benefits, including directorships | You are employed or a company director. Foreign employment income goes here, not on the foreign pages |
| SA103S / SA103F — Self-employment (short) / (full) | Sole trader profits. Short version where turnover was below the VAT threshold, full version above it | You trade on your own account, including most freelance work |
| SA105 — Self Assessment: UK property | Rental profits and losses from UK land and property | You let a UK property, including a former home let after you moved abroad |
| SA106 — Self Assessment: Foreign | Foreign income and gains, Foreign Tax Credit Relief, FIG regime relief | You have non-UK income, or need credit for foreign tax on income taxed in both countries |
| SA108 — Capital gains summary | Chargeable gains and allowable losses | You disposed of assets — shares, a second property, a business interest |
| SA109 — Residence and FIG regime etc | Residence status, split year, FIG claims, non-resident personal allowances | Any circumstance listed earlier applies |
HMRC's SA106 notes are unusually direct about where foreign income belongs, and both rules trip people up.
First, foreign employment income goes on the Employment pages. The foreign pages are used only to claim the foreign tax paid on that income; a US salary reported on SA106 instead of SA102 produces a return that reconciles against nothing.
Second, if you are resident abroad and completing the SA109, you should not complete the SA106 at all. A non-resident is charged to UK tax on UK-source income; foreign income sits outside the charge.
Foreign Tax Credit Relief is claimed on the SA106, and helpsheet HS263, "Relief for foreign tax paid", sets out how it is worked out. HMRC asks for the "double taxed income" figure — the amount actually taxable in the other country, which is not always the amount taxable in the UK.
Split-year treatment stops the year of a move being taxed as though you had been UK resident throughout. The default is that a UK resident pays UK tax as a resident for the whole tax year; where you arrive or leave partway through and meet one of the defined cases, the year splits into a UK part and an overseas part, and you are charged on the resident basis only for the UK part.
HMRC's notes identify eight cases:
Each case carries its own conditions, and the day-counting sits inside the Statutory Residence Test. Those thresholds are detailed and they interact, so a condensed version is the easiest thing in UK tax to get wrong: the authoritative source is HMRC's Residence and FIG Regime Manual at RFIG21000, which works through every case in turn.
On the form: put an X in box 3 if a case applies, enter in box 6 the date from which the UK part begins or ends, tick box 3.1 if more than one case applies, and — the step most often skipped — name the case in box 54, the "any other information" box. Split-year treatment is a claim with a narrative attached, and claiming it without saying which case applies invites an enquiry. Our guide on timing a move between the US and UK covers how that date shapes everything either side of it.
For a US citizen the UK return has a second life: it is the evidence that UK tax was paid, and that evidence supports the foreign tax credit claimed on Form 1116, "Foreign Tax Credit (Individual, Estate, or Trust)". The IRS allows a credit for income taxes imposed on you by a foreign country, and says that in most cases taking them as a credit rather than a deduction is to your advantage.
Two structural problems arise, and both are solved by filing the UK return properly rather than by anything clever on the US side.
The years do not line up. The UK tax year runs 6 April to 5 April; the US year is the calendar year. A UK return is never a drop-in schedule for a Form 1116, and the reconciliation needs to be documented and applied consistently year on year.
The figures have to agree. If the SA109 says you became UK resident on 1 September and the US return implies something different, you have two returns telling different stories about the same twelve months. Where the credit is limited and tax spills into later years, the position compounds rather than corrects itself; see our note on foreign tax credit carryovers.
Be clear, too, about what the UK return does not evidence. National Insurance contributions are social security contributions rather than UK income tax, and sit under the separate US-UK social security agreement rather than the foreign tax credit rules.
Take an American who moves to London and starts full-time work there on 1 September 2025. Her circumstances meet one of the split-year cases, so 2025-26 splits into an overseas part and a UK part beginning 1 September.
Her UK employment income in the UK part of the year is £60,000. For 2025-26 the personal allowance is £12,570, leaving £47,430 of income after allowances. The basic rate of 20% applies to the first £37,700 of that — £7,540. The remaining £9,730 falls in the higher rate band at 40% — £3,892. Her UK income tax for the year is therefore £11,432.
Her UK filing is an SA100, an SA102 for the employment income, and an SA109 recording the split-year case and the date of 1 September 2025, with the case named in box 54. Because the residence pages are in the mix, HMRC's free online service is closed to her: she files on paper to arrive by 31 October 2026, or uses software or an agent by 31 January 2027.
That £11,432 — not her gross salary, not her net pay, not her National Insurance — is the figure allocated across her US tax years and carried to Form 1116. The SA109 is what makes the allocation defensible, because it fixes the date her UK residence began.
The residence pages are not hard to complete once the analysis behind them is settled — and the analysis is usually settled months before anyone opens the form, by when you moved, where you worked and where you kept a home. If your year of arrival or departure is still open, or you are weighing a FIG claim against its US consequences, that is the point at which a conversation is worth more than a form.
Next Tax Source prepares both sides of a US-UK position in one engagement: the UK Self Assessment reviewed and signed off by an ACCA-qualified accountant, and the US return reviewed and signed off by a licensed CPA or Enrolled Agent, so the two tell the same story about the same year. We work as tax specialists for US and UK filers rather than treating one side as an afterthought, and the moving-year return is where that matters most. To have your position reviewed before the paper deadline, book a consultation.
General information about UK and US tax rules, not advice on your circumstances. Form titles, deadlines and figures are drawn from the official sources above and relate to the 2025 to 2026 UK tax year.