Moving to the UK from the USA: the 2026 tax guide

Answer first: yes on UK income from day one, and potentially on worldwide income once you are UK resident, but often not on your US income and gains for the first four years. The UK default (the arising basis) taxes a resident's worldwide income and gains as they arise. The big exception for new arrivers is the 4-year FIG regime covered below, which most Americans qualify for.

What does not change is the American side. The United States taxes on the basis of citizenship, not residence, so citizens and green card holders must keep filing and reporting worldwide income from the UK exactly as they did at home (IRS). Moving does not switch that off; only renouncing citizenship or formally surrendering a green card does, and both are serious steps with their own tax consequences. So the realistic picture is two returns a year, coordinated so the US-UK treaty and foreign tax credits stop the same income being fully taxed twice (GOV.UK treaty texts).

Alongside the tax returns, US information reporting follows you too: FBAR and FATCA will pick up your new UK bank accounts, pensions and investments once their thresholds are met, so the UK accounts you open in month one appear on US forms the following spring.

UK tax residence is not a choice and has nothing to do with your visa; it is decided mechanically by the Statutory Residence Test (RDR3, GOV.UK). The UK tax year runs 6 April to 5 April, and the main routes to residence are:

• 183 days or more in the UK in a tax year makes you automatically resident, with no exceptions. You are generally counted as present for a day if you are in the UK at midnight.
• The home test: broadly, being present on 30 or more days in a UK home that you have for a period of at least 91 consecutive days, with no sufficiently used overseas home, can make you resident on far fewer days.
• The full-time work test: working full time in the UK over a 365-day period can also make you resident.
• If no automatic test bites, the sufficient ties test weighs your UK connections (family, accommodation, work, 90-day history) against your day count.

Arrival timing matters more for Americans than for most nationalities because the two tax years are offset: the UK year starts on 6 April, the US year on 1 January. Arriving shortly after 6 April gives you a clean, nearly full first UK year, which makes residence, the FIG claim and the credit mapping onto your US calendar year simpler. Arriving late in the UK year can mean a short first resident period but burns one of your four FIG years for only a few months of benefit, because split years still count as full years for the FIG clock. Run your planned dates through the SRT calculator before you book anything.

When you arrive part-way through a UK tax year, split-year treatment can divide that year into an overseas part and a UK part, so you are taxed as a UK resident only from the point you arrive rather than for the whole year back to the previous 6 April. For arrivers the usual triggers are starting to have your only home in the UK, starting full-time work here, or starting to have a home in the UK; there is also a case for joining a partner who has returned after ceasing full-time work abroad.

Split-year treatment is not elective: if you meet the conditions it applies, and if you do not, you are resident for the whole year. Whether it applies, and from which date the UK part starts, can move real money, especially if you receive a bonus, exercise options or realise gains in the months before you land. The US side ignores all of this: your calendar-year Form 1040 reports everything regardless, which is exactly why the two returns need to be prepared with each other in view.

The 4-year Foreign Income and Gains regime (GOV.UK guidance) replaced the old non-dom remittance basis on 6 April 2025 and is the single most valuable UK relief for a new arriver. If you become UK resident after at least 10 consecutive tax years of non-UK residence, you can claim full UK relief on qualifying foreign income and gains for your first four UK-resident years, and you can bring the money into the UK freely. Anyone who has never been UK resident meets the 10-year test automatically, which is why most arriving Americans qualify; check yours with the FIG checker.

For an American the regime typically shelters US dividends, interest, rental profits and capital gains from UK tax during the window. UK-source income (a UK salary, UK rent) stays taxable from day one, and foreign employment income sits outside the FIG claim; it is relieved separately through Overseas Workday Relief where the conditions are met.

What claiming costs. You must claim each year on the SA109 pages of your Self Assessment return, and in any year you claim you give up your £12,570 Personal Allowance and your Capital Gains Tax annual exempt amount. With modest US income the lost allowances can outweigh the relief, so the claim should be modelled year by year, not assumed. And one point matters more for Americans than anyone else: FIG relieves UK tax only. The US still taxes the same income, and because FIG removes the UK tax there is no UK credit to set against the US bill on that slice. A FIG claim is therefore a two-country calculation, never a UK-only one.

On the US return there are two main ways to relieve double tax on your earnings. The Foreign Earned Income Exclusion (FEIE) excludes a capped amount of foreign earned income from US tax: $132,900 for the 2026 tax year, up from $130,000 for 2025 (IRS). The foreign tax credit (Form 1116) instead credits UK tax paid against US tax on the same income. You cannot claim a credit on income you have excluded under the FEIE, and once made the FEIE election generally stays in effect until revoked, so it is a decision with a tail, not a checkbox.

For most Americans employed in the UK the credit route works out better: UK income tax rates are generally higher than US rates, so the UK tax usually absorbs the whole US liability on the same salary and can generate carryover credits, and the FEIE only ever shelters earned income in any case. The handoff to watch is the interaction with FIG: income you shelter from UK tax under a FIG claim carries no UK tax to credit, so the US tax on it stands. Which mechanism to elect, and when, is a US-return decision that sits with your US preparer, made alongside the UK numbers rather than after them.

The best US-UK outcomes are set up before the SRT clock ticks over. Practical areas people commonly review with their advisers before departure:

• Account structures. Some US brokerages and fund platforms restrict or close accounts for UK-resident customers, and UK banks will report your new accounts under FATCA. Many people review with their advisers how each account will be treated once they are UK resident, and that review is far easier to run from a US address.
• PFIC exposure. Non-US pooled funds (UK OEICs, most UK and European ETFs, funds inside a stocks-and-shares ISA) are generally PFICs for US purposes, with punitive US tax and per-fund reporting. Many Americans review how any planned UK investments and ISAs would be treated on the US side before opening them.
• Timing of gains. Gains realised while you are still non-UK resident are generally outside UK tax, with UK land and property the main exception because non-residents pay UK CGT on that. Gains realised after arrival may rely on a FIG claim during the window and are fully exposed after it. The US taxes your gains either way, so the question is mostly about the UK layer and it is worth modelling before the move.
• State departure. Federal tax is only half the US picture. Each state sets its own residency rules, and some continue to assert residency until you clearly establish a new domicile elsewhere, so people commonly tidy up state ties (lease or sale, driving licence, voter registration) as part of leaving.
• Records. Note asset values and exchange rates at your arrival date and keep both countries' paperwork; UK and US computations will use different years, currencies and bases for the same events.

None of this is investment advice; it is sequencing. The same account or gain can be treated completely differently depending on which side of your arrival date it sits.

Payroll taxes are handled separately from income tax. Once you work in the UK for a UK employer you normally pay UK National Insurance through payroll, and the US-UK Totalization Agreement exists to stop you paying social security contributions to both systems on the same wages (IRS). Employees sent to the UK temporarily by a US employer can often stay in US Social Security for the assignment period by obtaining a certificate of coverage, while people who move permanently simply switch to National Insurance.

Your existing US Social Security credits are not lost by moving, and the agreement also governs how the two contribution records interact for benefit purposes, which is worth confirming with the Social Security Administration for your own record. Meanwhile your UK National Insurance record starts building towards the UK State Pension. This is an outline only; cross-border payroll setups, especially remote work for a US employer from the UK, need specific advice.

From your first UK-resident year you are likely to be in Self Assessment, because FIG and residence claims are made on the SA109 pages, and the SA109 cannot be filed through HMRC's free online service, so commercial software or an adviser is needed. The US return continues on its own calendar with special extensions for Americans abroad (IRS).

The rhythm that works is UK first, US second: the UK figures for the year to 5 April feed the foreign tax credit workings on the calendar-year US return. We prepare the UK side and supply the income and tax-paid figures our US partners need, so the credits line up instead of being reconstructed after the fact. Fixed fees are agreed upfront: non-resident and expat returns start from £550, complex cross-border cases from £750.