US taxes for Brits: the UK link and your State Pension

The US taxes its residents on their worldwide income, so once you're settled in New York, the IRS wants to know about every pound you have back home.

The short version

You become a US tax resident by holding a green card or by passing the substantial presence test: broadly 183 weighted days over three years, with at least 31 in the current year [1].
US residents are taxed on worldwide income. In 2026, federal rates run from 10% to 37%, with a standard deduction of US$16,100 (about £11,950) for a single person [2]. New York State and City tax come on top.
On the UK side, leaving properly means the Statutory Residence Test, split-year treatment and a P85 or Self Assessment return. UK income such as rent can stay taxable in the UK [3][4].
Under the UK–US double taxation treaty, your UK State Pension is taxable only in the US while you live there, and UK private and workplace pensions are generally taxed where you live [5].
If your non-US accounts add up to more than US$10,000 (about £7,420) at any point in the year, you must file an FBAR [6].

When you become a US tax resident

Two tests decide it [1]:

The green card test. Hold a green card at any point in the year and you're a resident.
The substantial presence test. You're resident if you were in the US for at least 31 days this year and at least 183 days over three years, counting all of this year's days, a third of last year's and a sixth of the year before.

Some days don't count. Students on F or J visas, teachers and trainees on J visas, and diplomats are "exempt individuals" for this purpose, and generally have to file Form 8843 to say so [1]. There's also a "closer connection" exception for people who pass the test but are clearly based elsewhere [1].

The US tax year is the calendar year, and returns are due on 15 April. The UK's runs from 6 April to 5 April. That mismatch makes your first and last years fiddly: many people are a "dual-status" taxpayer in the year they arrive, partly non-resident and partly resident.

How much the IRS takes

The 2026 federal rates for a single person, after the standard deduction, are [2]:

Rate	Taxable income (single, 2026)	In pounds
10%	Up to US$12,400	up to about £9,200
12%	US$12,400 to US$50,400	about £9,200 to £37,400
22%	US$50,400 to US$105,700	about £37,400 to £78,440
24%	US$105,700 to US$201,775	about £78,440 to £149,730
32%	US$201,775 to US$256,225	about £149,730 to £190,130
35%	US$256,225 to US$640,600	about £190,130 to £475,360
37%	Over US$640,600	over about £475,360

The standard deduction is US$16,100 (about £11,950) for a single person and US$32,200 (about £23,890) for a married couple filing jointly [2]. Compare the UK's Personal Allowance of £12,570, basic rate of 20% up to £50,270, higher rate of 40% and additional rate of 45% over £125,140 in 2026/27 [7].

Then add New York State and New York City income tax, plus Social Security and Medicare taxes withheld from your pay. Our guide to New York State and City income tax covers those layers and what happens if you live in New Jersey or Connecticut instead.

Leaving the UK tax system properly

The UK taxes by residence, not citizenship, so once you've moved you can usually stop paying UK tax on your new US salary. But you need to leave properly:

Check the Statutory Residence Test. It decides if you're UK resident for each tax year. See the Statutory Residence Test explained.
Look at split-year treatment. It can split the year you leave into a UK part and an overseas part. Our split-year guide has the cases.
Tell HMRC. Use form P85 if you were employed and won't file a Self Assessment return for that year [4]. Otherwise you report leaving on your return, with the SA109 residence pages.
Keep an eye on UK income. Non-residents usually still pay UK tax on UK income such as rent, and you'll usually need Self Assessment if you let out a UK property [3]. Non-residents who file can't use HMRC's online service and must post the SA100 and SA109, use commercial software, or use an agent, with a paper deadline of 31 October [3].

Our guide to UK income while you live abroad covers rent, savings and the Non-Resident Landlord Scheme.

The UK–US treaty: who taxes what

The treaty, in force since 31 March 2003 and amended by a 2002 protocol, stops the same income being fully taxed twice [5]. The FCDO points readers to the IRS for questions on double taxation relief [8]. The key bits for Brits in New York:

Income	Who taxes it under the treaty	Article
UK State Pension, paid to a US resident	Only the US	Article 17(3)
UK workplace and private pensions	Generally only the country where you live	Article 17(1)(a)
Lump sums from a UK pension scheme	Only the UK, for a US resident	Article 17(2)
Income taxed in both countries, such as UK rent	Both, with a credit for the other country's tax	Article 24

Source: the UK–US Double Taxation Convention as amended, on GOV.UK [5].

A US resident's UK State Pension is taxable only in the US. Article 17(3) says social security payments made by one country to a resident of the other country are taxable "only in that other State" [5]. So the IRS taxes it and HMRC doesn't. Article 1 lets the US tax its citizens and residents as if the treaty didn't exist (the "saving clause"), but Article 17(3) is one of the listed exceptions, so the rule holds even if you become a US citizen [5].

Pensions in payment from a UK scheme are generally taxable only where you live [5]. Lump sums have their own paragraph and the interaction with the UK's tax-free lump sum is technical. A tax adviser who knows both countries can check how the rules apply to your scheme before you draw anything. Never move a UK pension into a US plan without regulated financial advice; our guide to UK pensions abroad and the transfer warnings explains why.

Where both countries can tax, as with rent from a flat in Manchester, the treaty's relief article gives a credit: the US allows a credit for UK tax paid, and the UK credits US tax on US-source income [5].

Your State Pension: uprated in the US

Good news for once. The US is on the DWP's list of countries with a social security agreement where the UK State Pension goes up every year, so it isn't frozen as it would be in Australia or Canada [9]. The full new State Pension is £230.25 a week in 2025/26 and £241.30 a week in 2026/27 [10].

You claim it from abroad through the International Pension Centre, and it's taxed in the US as above. If you're filling gaps in your National Insurance record, see voluntary National Insurance from abroad, and for how it fits with US Social Security, our guide to the UK State Pension and US Social Security.

The traps: ISAs, UK funds and reporting

ISAs aren't tax-free in the US. The IRS taxes ISA interest, dividends and gains like any other investment income. The UK still treats the ISA as tax-free, but you can't pay into it once you're non-UK resident.
UK funds can be PFICs. UK unit trusts, OEICs and many ETFs count as "passive foreign investment companies" for a US resident, with punishing tax and paperwork. Our guide to ISAs, UK pensions and PFICs goes through the options.
FBAR. If the combined value of your non-US accounts tops US$10,000 at any time in the calendar year, you file an FBAR by 15 April, with an automatic extension to 15 October. It goes electronically to FinCEN, not with your tax return [6]. Your UK current account, savings and ISA all count.
FATCA. Bigger foreign holdings also go on Form 8938 with your return; the thresholds depend on your situation.

If your partner is American, our sister site ExpatStateside explains filing status and taxes when you're married to a non-American, which matters if you file jointly.

Questions like this come up in our community group for Brits in the US all the time, and you can join here.

Pound conversions use the Bank of England spot rate of 5 November 2026 (£1 = USD 1.3476). Tax is general information, not advice; a tax adviser who knows both countries can check your situation.

US taxes for Brits: residence, the UK–US treaty and your State Pension