Resourcing Income by Treaty: Claiming a US Credit for UK Tax

Resourcing by treaty is the mechanism that lets a US citizen living in Britain claim a foreign tax credit for UK tax on income the US insists is American. The US-UK Convention's relief-from-double-taxation article deems that income to arise outside the United States, but only for credit purposes, only to the extent needed to stop the same income being taxed twice, and only if you elect to apply the treaty. It is a sized calculation, not a switch — which is why it rarely produces the spare credits people expect.

Key takeaways

The foreign tax credit is limited by reference to foreign-source income. Income the US sources to the US creates no room in that limitation, so UK tax on it has nothing to offset.
The Convention's relief article re-sources that income for credit purposes. It does not make the income British for any other purpose, and it does not reduce the US tax the Convention lets America keep as the country of source.
Resourcing happens only to the extent necessary. The Technical Explanation's own worked examples end with no excess credit available to carry over — a result almost no published guide warns about.
Most guides tell you to report this in the Form 1116 category for certain income re-sourced by treaty. For a US citizen resident in the UK that is probably wrong: the separate-limitation rule has an express exception for relief articles that apply solely to citizens resident in the treaty country.
A resourcing position is a treaty-based position. Whether it needs separate disclosure is a judgement call, and the published advice genuinely conflicts.

First, which direction the resourcing runs

The phrase people search for — resourcing UK income to get a US credit — gets the direction backwards, and the confusion matters.

The income in question is US-source under US rules: dividends from American companies, interest from American payers, rent from an American property, gains the US sources to itself. You live in Britain, so HMRC taxes that income as it arises. The US taxes it too, because you are a citizen. You reach for Form 1116, and it does nothing, because the credit limitation is a ratio built on foreign-source income and this income is not foreign-source.

Resourcing fixes that by deeming the US-source income to arise in the UK. Nothing moves the other way. If your income were genuinely UK-source — a British salary, a British rental — you would never need resourcing at all; the ordinary credit rules already work, and the question becomes which UK taxes actually qualify, which we cover in which UK taxes are creditable on a US return.

What the relief article actually does

In the US-UK Convention the relief from double taxation article runs in two halves: the earlier paragraphs govern relief the United States gives, the later ones relief the United Kingdom gives. The special rules for a US citizen who is resident in Britain sit in paragraph 6, and they work in sequence.

Sub-paragraph (a) confirms that Britain need not credit US tax on income from sources outside the United States. As between the country of residence and the country of citizenship, residence takes priority.
Sub-paragraph (b) caps the UK credit. For US-source income that would have been exempt or reduced in American hands had you been a UK resident who is not a US citizen, the credit HMRC must give need not exceed the US tax the Convention itself permits — ignoring the extra tax America charges purely because of your citizenship.
Sub-paragraph (c) then closes the gap that (b) deliberately leaves open. The United States credits the UK tax, computed after (b) has been applied. Crucially, in giving that credit America will not reduce its tax below the amount Britain took into account under (b).
Sub-paragraph (d) is the resourcing rule. Because the income described in (b) is US-source, it has to be deemed foreign for the US credit to be computable at all — and (d) does exactly that, to the extent necessary to relieve the double taxation that (c) addresses.

Read in order, the architecture is deliberate: the Convention lets America keep a defined slice of tax as the country of source, requires Britain to credit only that slice, and then resources just enough income for America to credit whatever UK tax is left standing. The sequencing is set out, paragraph by paragraph, in the Treasury Technical Explanation of the Convention, and the Convention as enacted in UK law sits on legislation.gov.uk.

How much income gets re-sourced

This is the part that is almost never explained, and it is where returns go wrong.

Resourcing is not "tick a box and the income becomes foreign". The amount re-sourced is computed: you work out how much UK tax you are entitled to credit, then re-source only as much income as it takes to generate that much US limitation at your own US effective rate. If the UK tax is small relative to the US tax, a modest slice of income moves. If the UK tax is large, the slice is bigger — but it is still capped, because sub-paragraph (c) will not let the US credit erode the source-country tax the Convention reserved to America.

The Technical Explanation works this through twice, once where the UK rate sits below the US rate and once above it. Both examples are worth reading in the original rather than paraphrase, because the arithmetic is the explanation.

The consequence nobody writes down: no spare credits

Because resourcing is sized to the job, it does not manufacture excess credit.

The Technical Explanation's second example is explicit about it: the UK tax exceeded the US tax available for credit, and there was still no excess credit available for carryover. The resourcing stopped at the cap, so the unrelieved UK tax simply stayed unrelieved rather than becoming a carryforward.

That matters for planning. People expect a high-UK-tax year to bank credits they can carry into a later year, the way surplus credits on genuinely foreign income do. On resourced income under this article, they generally will not — the cap bites first. If your position depends on banking credits, the general rules on baskets and carryovers in foreign tax credit carryovers for US expats describe how that works for ordinary foreign income, and the difference is the point.

Carryback and carryforward windows for foreign taxes are statutory and change rarely, but we do not hold a verified current figure for them, so confirm the periods for your own year before relying on them.

What resourcing does to the Form 1116 basket

Here is where the published guidance and the IRS's own position diverge.

Form 1116 has a category for certain income re-sourced by treaty, and the rule attached to it is that you must compute a separate credit limitation for such income, on a separate Form 1116 for each amount of re-sourced income from each treaty country. Almost every guide stops there and tells the UK-resident American to file an extra Form 1116 in that category.

But the rule carries an exception. Publication 514 states it directly: the rule "does not apply to income that is re-sourced by reason of the relief from double taxation rules" in any US income tax treaty "that is solely applicable to U.S. citizens who are residents of the foreign treaty country." The Form 1116 instructions carry the same exception.

Paragraph 6 of the US-UK relief article is precisely that kind of provision. It applies solely to US citizens who are resident in the United Kingdom. The IRS's own training material on this category — the transcript of its Form 1116 re-sourced income session — puts it in one line: income re-sourced under this rule "doesn't actually go into the treaty basket."

The practical effect is that the resourced income is reported in the basket the income belongs to by character — passive, usually — rather than quarantined in its own category and limitation. That is the opposite of the common advice, and it changes the credit you compute, because a separate limitation and a shared one give different answers.

This is a genuinely technical point on which competent advisers can land differently depending on how they read the relief article. We think the exception plainly covers the UK position, but it is exactly the sort of conclusion that should be reasoned on your own facts and documented, not copied from a blog — including this one.

The disclosure that goes with it

Resourcing depends on electing to apply the treaty, and a position that relies on a treaty to override how the Code would otherwise treat an item is a treaty-based return position. Published guidance divides on whether resourcing needs a separate disclosure on its own: some practitioners disclose every resourcing position as a matter of course, others take the view that claiming a credit the Code already provides, on income the treaty merely re-sources, is not an override at all.

We do not restate the disclosure mechanics here — the thresholds, the waivers, the line-by-line drafting and the penalty exposure are set out in when to disclose a US-UK treaty position on Form 8833. What belongs in this article is the narrower judgement: whether resourcing under this particular article crosses the line, and if the answer is arguable, that disclosing is cheap and silence is not.

Where we fit

Resourcing is one of the few places in a US-UK return where the right answer depends on reading four documents together — the Convention, its Technical Explanation, the Form 1116 instructions and your own UK computation — and where every shortcut in general circulation points the wrong way. We work the UK computation first so the creditable UK tax is a real number, then size the resourcing against it, then decide the basket question on your facts and write down the reasoning so next year's return is consistent with this one.

Every return and every form we prepare is reviewed and signed by a licensed professional — an IRS Enrolled Agent who is also ACCA-qualified — so the US credit computation and the UK Self Assessment behind it are looked at by one person rather than two who never speak. You can read more about how we handle this work on our US-UK tax specialists page, see what it costs, book a consultation, or model your own position first with our calculators.

Nothing above is a figure you can rely on for your own year, because resourcing is a mechanism rather than a rate. Confirm the current credit carryover windows, the Convention's withholding ceilings and the Form 1116 category letters for the year you are filing before you act.

Frequently asked questions

How do I enter income under the "resourced by treaty" category on Form 1116?+

You identify the amount of income the treaty re-sources — not the whole item, only as much as is needed to generate the credit you are claiming — and report it with the foreign tax that attaches to it. The category question is the one to settle first. Form 1116 has a dedicated category for certain income re-sourced by treaty, carrying its own separate credit limitation, but that rule has an express exception for resourcing under a relief article that applies solely to US citizens resident in the treaty country. The US-UK relief article is that kind of provision, so for a US citizen in Britain the resourced income will usually belong in the basket its character dictates rather than in the separate treaty category. The category letters move between form years, so check the current form and its instructions rather than last year.

Income re-sourced by treaty: is Form 8833 required?+

The published advice genuinely conflicts, and the honest answer is that it depends on how you characterise the position. One view is that resourcing overrides the Code sourcing rules and is therefore a treaty-based position requiring disclosure. The other is that the credit itself comes from domestic law, the treaty only changes where the income is treated as arising, and nothing is being overridden. Disclosure costs very little and omitting a required one carries a penalty, so the asymmetry favours disclosing where the answer is arguable. The thresholds, the waiver list and the drafting are set out in our article on disclosing a US-UK treaty position on Form 8833.

Can a US citizen living in the UK claim a foreign tax credit on US dividends?+

Not under the ordinary rules, because dividends from US companies are US-source and the credit limitation is built on foreign-source income. The relief article in the US-UK Convention is what makes a credit possible: it caps the credit HMRC must give to the tax the Convention lets America charge a UK resident who is not a US citizen, then re-sources enough of the dividend to the UK for America to credit the UK tax left standing. The credit is real but partial by design — the Convention deliberately leaves America a slice of tax as the country of source, and that slice is not creditable.

In what order do the US and UK credits apply?+

Britain goes first. As the country of residence it gives credit for US tax, but only for the amount the Convention would have permitted America to charge a UK resident who is not a US citizen — not the full citizenship-based US tax. Whatever UK tax remains after that is then credited by the United States, which is why the resourcing rule exists at all: without it the income would still be US-source and there would be no limitation room to credit against. The United States will not, in giving that credit, reduce its own tax below the amount Britain already took into account.

What if I never claimed the treaty, and now I think I should have?+

Amended returns are the normal route, and claims for a foreign tax credit have their own limitation period which is longer than the general one for refunds — we do not quote the period here because it should be confirmed for your year before you rely on it. Two practical points. First, work out whether resourcing would actually have helped: if the cap would have bitten, the recoverable amount may be smaller than you expect. Second, decide the basket and disclosure questions for the amended years on the same reasoning you will use going forward, so the open years and the current one are consistent.