Saving Clause Exceptions: What the US-UK Treaty Still Gives Americans

The saving clause exceptions are the treaty benefits a US citizen can still claim against US tax. Article 1(4) of the 2001 UK-US Income Tax Treaty lets the United States tax its citizens as if the treaty did not exist. Article 1(5) then lists the exceptions. For Americans in the UK, the key ones cover pension lump sums, Social Security, UK pension schemes, relief from double taxation, non-discrimination and the mutual agreement procedure.

Many Americans in Britain hear that "the treaty does not apply to US citizens" and stop reading. That is too broad. The saving clause removes most benefits, but the exceptions that remain are some of the most valuable provisions in the whole treaty. This guide lists them, explains what each one does in practice, and shows when a claim must be disclosed. It does not cover the UK side of the treaty, where a UK resident can rely on the articles in the normal way.

What the saving clause does

Article 1(4) says that, apart from the exceptions in paragraph 5, a country may tax its residents, and by reason of citizenship its citizens, as if the treaty had not come into effect. Because the US taxes on citizenship, this clause preserves full US taxing rights over Americans living in the UK. The treaty text is published on the IRS United Kingdom tax treaty documents page.

Why it catches people out

Consider Article 17(1)(a). It says a pension is taxable only in the recipient's country of residence. A British citizen living in London can rely on that against the US. A US citizen living in London cannot, because the saving clause overrides it. As a result, the same sentence of the treaty produces two different answers depending on citizenship.

The saving clause exceptions in Article 1(5)

Article 1(5) contains two lists. The first applies to everyone, including US citizens. The second applies only to people who are neither US citizens nor US green card holders.

Always confirm the precise paragraph against the treaty text and the 2002 protocol, which HMRC also publishes on its USA: tax treaties page, before relying on it, because small drafting details change the outcome.

What the main saving clause exceptions mean in practice

Four of the exceptions matter to most Americans in Britain.

Article 17(1)(b): the UK pension lump sum

The UK lets most people take 25% of a pension as a tax-free lump sum. Article 17(1)(b) exempts in one country a pension amount that would be exempt in the other if the recipient were resident there. Because this paragraph survives the saving clause, many advisers take the position that the UK tax-free lump sum is also exempt from US tax. The position is widely used but not free from doubt, so it should be documented. Our guide to the UK pension lump sum and US tax sets out the argument.

Article 17(3): Social Security

Social security benefits paid by one country to a resident of the other are taxable only in the country of residence. For a US citizen resident in the UK, that means US Social Security is taxed by the UK and not by the US. This is one of the clearest saving clause exceptions. Our guide to US Social Security for UK residents covers how to report it.

Article 18: growth and contributions in UK pensions

Article 18(1) defers tax on income earned inside a pension scheme until distribution. Article 18(5) goes further for US citizens resident in the UK. It allows US relief for contributions to a UK scheme and stops employer contributions and accrued benefits being taxed as current US income, up to the limits that would apply to a comparable US plan. Without these two paragraphs, a workplace pension or SIPP could create US tax every year.

Article 24: relief from double taxation

Article 24 guarantees a foreign tax credit and, importantly, re-sources certain US-source income as foreign for US citizens resident in the UK. That re-sourcing rule is what lets UK tax on US dividends or interest be credited. It is covered on our foreign tax credit and double taxation page.

Disclosing a treaty position on Form 8833

If you take a treaty position that overrides or modifies the Internal Revenue Code and reduces your tax, section 6114 generally requires disclosure on Form 8833. The penalty for failing to disclose is $1,000 for an individual under section 6712. Some positions are exempt from disclosure under the regulations, including certain reductions in tax on pensions and Social Security. However, re-sourcing claims under Article 24 generally do need disclosure. Our guide to when Americans in the UK file Form 8833 lists the common cases.

An illustrative case

Consider an illustrative US citizen who has lived in Edinburgh for 20 years and retires in 2026. The facts are illustrative. She draws US Social Security, takes a 25% lump sum from her UK workplace pension and then begins drawdown. Under Article 17(3), her Social Security is taxable only in the UK. Under Article 17(1)(b), her adviser treats the lump sum as exempt from US tax and documents the position. The drawdown income has no exception: the saving clause applies, so the US taxes it and she claims a foreign tax credit under Article 24 for the UK tax. Three payments, three different treaty outcomes.

Common mistakes

First, assuming no treaty benefit is available to a US citizen. Second, the opposite error: claiming Article 17(1)(a) or another residence-based article against US tax. Third, relying on an exception without checking whether Form 8833 is required. Finally, overlooking that the UK-UAE and US positions differ entirely, because the US has no income tax treaty with the UAE. Our cross-border taxation page explains how residence and citizenship interact across all three countries.

If you are unsure which treaty benefits you can claim, book a consultation with our US-UK treaty team. We identify the saving clause exceptions that apply to you and document each position properly.

Frequently Asked Questions

What is the saving clause in the US-UK tax treaty?

The saving clause is Article 1(4) of the 2001 UK-US Income Tax Treaty. It allows each country to tax its residents, and the United States to tax its citizens, as if the treaty had not come into effect. It is why most treaty articles do not reduce US tax for Americans living in the UK.

What are the saving clause exceptions?

The saving clause exceptions are the benefits listed in Article 1(5) that US citizens can still claim. They include Article 17(1)(b) on exempt pension amounts, Article 17(3) on Social Security, Article 18(1) and 18(5) on pension schemes, Article 24 on relief from double taxation, Article 25 on non-discrimination and Article 26 on the mutual agreement procedure.

Does the US tax Social Security paid to a US citizen living in the UK?

Generally no. Under Article 17(3) of the US-UK tax treaty, social security benefits are taxable only in the country of residence, and this paragraph is an exception to the saving clause. A US citizen resident in the UK therefore reports US Social Security to HMRC rather than paying US tax on it.

Is the UK 25% pension lump sum taxable in the US?

Many advisers treat it as exempt under Article 17(1)(b), which survives the saving clause. That paragraph exempts a pension amount in one country if it would be exempt in the other for a resident there. The IRS has not confirmed the position in published guidance, so it should be documented and reviewed on the specific facts.

Do I need Form 8833 to claim a saving clause exception?

Sometimes. Internal Revenue Code section 6114 requires disclosure of treaty-based return positions on Form 8833, with a $1,000 penalty for individuals who fail to file. Certain pension and Social Security positions are exempt from disclosure under the regulations, but re-sourcing claims under Article 24 generally are not.

Can a green card holder in the UK use the saving clause exceptions?

Yes, for the first list in Article 1(5), which applies to everyone. The second list, covering Articles 18(2), 19, 20, 21 and 28, is available only to individuals who are neither US citizens nor admitted for permanent residence in the United States.