Specialist US UK Tax Services: Paid or Accrued FTC Basis

A US taxpayer in the UK claims the foreign tax credit either when the UK tax is paid or when it accrues. The accrued basis requires an election that is irrevocable and binds every later year. For a late filer catching up several years at once, that choice is made in the earliest return and governs the whole package.

This is one of the least discussed and most expensive decisions in cross-border compliance. Most published guidance treats the "Paid" and "Accrued" boxes in Part II of Form 1116 as a formatting question. They are not. They are a permanent structural election that determines how much UK tax you can actually use against US liability in each year of a catch-up, how much spills into carryforward, and whether your submission tells a coherent story to an IRS reviewer. At Jungle Tax, Specialist US UK Tax Services begin with this election precisely because it cannot be walked back once the first return in a catch-up is signed.

What do the paid basis and the accrued basis actually mean?

Almost every individual is a cash-method taxpayer. The default rule follows from that: you credit a foreign income tax in the US tax year in which you hand the money over. Pay HMRC on 28 January 2026, and that payment is a 2026 credit, regardless of which UK tax year generated the liability.

The accrued basis works from a completely different anchor. Under the regulations at §1.905-1, foreign net income taxes accrue at the close of the foreign taxable year, and an accrual-basis claimant takes the credit in the US tax year with or within which that foreign taxable year ends. The UK tax year ending 5 April 2026 ends inside US calendar 2026, so the entire UK 2025/26 liability is a 2026 credit — irrespective of when a penny of it is actually remitted.

Two points follow immediately, and both are routinely missed:

• The accrual basis is an election, not a description of your bookkeeping. A cash-method individual does not "become" accrual-basis by nature of holding UK income. The election is made affirmatively by checking the "Accrued" box in Part II of Form 1116.
• The election is irrevocable and applies to all foreign taxes in all later years. It is not a per-country, per-basket or per-year toggle. Once made, it governs your general basket, your passive basket, and any other jurisdiction you later touch.

Withholding is the important exception to the first rule. Tax withheld at source — PAYE on employment income, or treaty-rate withholding on dividends — is treated as paid at the moment of withholding. For a straightforward PAYE employee with no Self Assessment balancing payment, the paid and accrued bases converge closely and the election is low-stakes. The moment there is a Self Assessment liability of any size, they diverge sharply.

Why does this election matter more for a late filer than for anyone else?

Because of when it can be made, and because a catch-up compresses the whole decision into a single moment.

The one-shot rule in the regulations

The general rule is that the election to claim credits on the accrued basis must be made on a timely filed original return. Treasury declined to allow taxpayers to reach back and switch method retroactively on amended returns, on the reasoning that a retroactive change ripples through carryovers, limitation calculations and closed years.

There is a narrow and enormously important exception. A taxpayer who has never previously claimed a foreign tax credit may make the accrual election on an amended return. That exception exists almost as if it were drafted for the profile we see constantly: the accidental American, the UK-resident founder who never realised a US return was required, the executive who was told by a UK adviser that PAYE settled everything. Someone with no filing history has never claimed a credit, so the door is open.

But the door closes on itself. The moment the earliest return in your catch-up claims a credit on the paid basis, you have claimed a foreign tax credit. Every subsequent year in the package — and every year after the package — must follow that basis. This is why we describe the choice as being effectively locked once made: a three-year streamlined submission is not three independent decisions, it is one decision applied three times.

What this means inside a streamlined submission

The Streamlined Filing Compliance Procedures require three years of federal income tax returns and six years of FBARs. For a non-resident US person under the Foreign Offshore Procedure, those three years are frequently delinquent originals rather than amendments — the taxpayer simply never filed. That produces a technical question the generalist pages never confront: a delinquent original return is not a "timely filed original return," and the regulatory exception is framed around amended returns.

In practice, a first-ever claimant filing delinquent originals is generally treated as able to elect the accrued basis, because the policy concern the exception addresses — a taxpayer with no prior credit history and therefore no carryover chain to disturb — is squarely met. But it is a position, and it should be taken deliberately, documented in the working papers, and supported by a consistent election statement across all three returns. It is not something to discover after the package has been posted. Our streamlined filing specialists settle this in the first modelling pass, before a single Form 1116 is populated.

How the UK tax calendar collides with the US tax year

The mechanical cause of the whole problem is that the two systems do not share a clock, and they do not share a payment rhythm.

Feature	United States (IRS)	United Kingdom (HMRC)
Tax year	Calendar year, 1 January to 31 December	6 April to 5 April
Default credit timing	Year the foreign tax is paid (cash method)	Credit relieved against the UK liability for the year the income is charged
Elective alternative	Accrued basis election under Form 1116 Part II — irrevocable	No equivalent basis election; relief follows the year of charge
Main settlement date	Balance due 15 April following year end	Balancing payment 31 January after the tax year ends
Instalments	Quarterly estimated tax	Payments on account 31 January and 31 July
Withholding at source	Federal withholding on US wages	PAYE, deducted through the UK year
Unused relief	Carry back 1 year, carry forward 10 years, per basket	Generally no carryforward of excess credit relief
Claim window	Extended period for refund claims attributable to foreign taxes	Generally four years from the end of the UK tax year

Work through the consequence. UK tax on the 2025/26 year is settled by a balancing payment on 31 January 2027, preceded by payments on account on 31 January 2026 and 31 July 2026. On the paid basis, that single UK year's tax is smeared across US 2026 and US 2027, and the balancing payment lands nearly ten months after the US year it economically belongs to has closed. On the accrued basis, the whole UK 2025/26 liability sits in US 2026, alongside the income that produced it.

For a client with steady income, the paid basis eventually reaches a rolling equilibrium and the mismatch is cosmetic. For anyone with a lumpy year — a bonus, a carried interest allocation, an EMI or share-scheme exercise, a property disposal, a business exit — the paid basis systematically strands credit. The income is taxed in the US in year one; the UK tax largely arrives in year two; and the credit limitation in year two may be far too small to absorb it.

A worked illustration across a three-year catch-up

Consider a UK-resident US citizen with steady employment income throughout, plus a substantial Self Assessment liability arising from a single large event in the middle UK year of the catch-up window.

• Paid basis. Year one carries only PAYE and the payments on account then falling due. Year two carries PAYE plus the January payment on account. Year three is overloaded: it absorbs the balancing payment on the event year plus recalibrated payments on account. Year three has abundant credit and comparatively little US-taxed foreign income to apply it against, so a large excess credit falls into carryforward. Year two, which carries the US tax on the event, has too little credit. The result is US tax payable in year two and dormant credit in year three.
• Accrued basis. The UK liability on the event year is assigned in full to the US year in which that UK year ends — which is the same US year that carries the bulk of the event income. Credit and income meet. The excess-credit position largely disappears, and the cash outcome across the three years can differ by a material sum.

The direction is not always that way. Where a client's income is falling, or where they are leaving the UK, the paid basis can be preferable because it delays credit into a year where it can be paired with residual US-taxed income. Where a taxpayer expects to abandon UK residence mid-window, the accrued basis can consolidate credit into a year that ends up with little foreign source income, wasting it. The point is that the answer is client-specific and must be modelled — and, critically, modelled once, before year one is filed.

Exchange rates: the quiet second effect

Basis also determines translation. Taxes claimed on the paid basis are translated at the spot rate on each date of payment. Taxes claimed on the accrued basis are generally translated using the average exchange rate for the US tax year to which they relate, with a separate election available to translate at the rate on the date of payment.

In a period of sterling volatility, this is not a rounding difference. A catch-up spanning several years of GBP/USD movement can see the same underlying UK liability produce meaningfully different dollar credits depending on the basis. The average-rate approach also removes an administrative burden that late filers underestimate: reconstructing spot rates for every historic HMRC payment, including payments on account made from a UK current account years ago, when bank records may no longer be readily available.

Carryforwards, carrybacks and Schedule B in a catch-up

Unused credits generally carry back one year and forward ten, tracked separately by basket. Since 2021, Schedule B to Form 1116 reconciles those carryovers year to year, and the IRS treats it as the running record of your credit history.

A catch-up has a structural problem here. The carryback from the earliest year in a streamlined package points at a year outside the package — frequently a year with no return on file at all. You cannot mechanically carry a credit back into a void. Equally, credits from years before the window can generally only be brought forward where there is a filed return establishing them. Practically, this means:

• Schedule B must be built from the first year forward, with an opening position that is honest about what does and does not exist.
• Any decision to expand the catch-up beyond the minimum three years — sometimes worthwhile precisely to establish carryforward — changes the basis analysis, because it changes which year is "first".
• An excess-credit position generated by the wrong basis choice is not a harmless deferral. Credits expire, and clients whose UK connection is ending may never generate the foreign source income needed to use them.

What happens if HMRC changes the number afterwards?

This is the accrual basis's genuine cost, and honest advice has to name it. If you accrue a UK liability and the final figure differs — an HMRC enquiry, an overpayment relief claim, a late amendment to a Self Assessment return, a repayment of an over-collected payment on account — you have a foreign tax redetermination. That obliges you to revisit the US year in which the tax was credited, and in most cases to file an amended return, with Schedule C to Form 1116 used to report current-year redeterminations.

Late filers are disproportionately exposed to this, because a catch-up on the US side is very often accompanied by remedial work on the UK side. If UK returns for the same years are being corrected or filed late, accruals are being set against numbers that may still move. A cash-basis claim, by contrast, credits only what has actually left the bank account, and is far more stable.

The practical resolution is sequencing. Where UK and US catch-ups run together, we normally want the UK position finalised, or at least stable and evidenced, before the US accrual election is committed. Where UK exposure is genuinely open — an active enquiry, a contested assessment — the paid basis often earns its place, and contested amounts are in any case not creditable until the contest is resolved and the tax is actually paid.

Is proration a third option?

It is common to see UK liability apportioned across the US calendar year — three-twelfths to one year, nine-twelfths to the next — on the theory that this "matches" the two calendars. This convention is widespread, but it is worth being clear that it is not what the accrual regulation says. The regulation assigns a foreign year's income tax to the single US year in which the foreign year ends. Proration is more defensible as a method for allocating foreign source income to a US year than for allocating the tax accrual itself.

Where we see this go wrong is the hybrid: a prior preparer prorated the UK tax across two US years while ticking "Paid" in Part II. That is internally inconsistent — the paid basis is keyed to actual remittance dates, not to a calendar apportionment — and it is exactly the kind of inconsistency that undermines a non-willfulness narrative if a streamlined package is later examined. Whatever basis is chosen must be reflected consistently in the box ticked, the amounts entered, the translation rates used and the working papers behind them.

The UK mirror: how HMRC handles the other direction

Clients often assume there is a symmetrical election on the UK side. There is not. UK foreign tax credit relief, set out in HMRC's helpsheet HS263, gives relief against the UK liability for the year in which the income is charged to UK tax, limited to the lower of the foreign tax properly payable under the treaty and the UK tax on the same income. There is no paid-versus-accrued election, and generally no carryforward of unrelieved credit.

That asymmetry has a consequence that matters for high-net-worth clients with US-source income: an excess on the UK side is usually lost outright, whereas an excess on the US side survives for up to ten years. Where relief is genuinely at risk of being wasted, the answer is rarely the basis election alone — it is treaty resourcing under the US-UK double tax agreement, correct basket allocation, and sequencing of income events. Our UK tax services and cross-border coordination work is built around keeping both sides of that calculation consistent, so the same pound of tax is neither claimed twice nor relieved nowhere.

How should the decision actually be made?

A disciplined process looks like this:

• Build a dual ledger. Every UK tax figure recorded twice: once by UK tax year of charge, once by actual date of payment, with PAYE separated from Self Assessment and payments on account separated from balancing payments.
• Extend the horizon beyond the catch-up window. The election binds future years, so model at least two to three years past the last catch-up return, including any known event — a liquidity event, a planned departure, a pension commencement, a trust distribution.
• Run both bases across the full horizon. Compare not just tax payable per year but the closing carryforward by basket and its realistic usability.
• Stress-test the UK numbers. If any year could still move, weight that against the accrual basis or delay until it settles.
• Document the election. Tick the correct box in Part II of every Form 1116 in the package, apply consistent translation, and retain a memorandum recording why the basis was chosen and that it was made by a first-time claimant.

Errors we most often correct

• Three streamlined returns filed with inconsistent boxes ticked across the years — the single most damaging error, because it is visible on the face of the package.
• Accrual claimed on returns for a taxpayer who had previously filed and claimed credit on the paid basis, making the election invalid rather than merely unwise.
• UK payments on account credited twice: once when paid and again when the balancing payment is computed gross.
• Credit claimed for UK tax on income excluded under the foreign earned income exclusion, which is not creditable.
• Class 2 and Class 4 National Insurance treated as creditable income tax, when the correct route is the US-UK totalization agreement and a certificate of coverage.
• Schedule B carryovers reconstructed by working backwards from a desired answer rather than forwards from a filed position.
• Spot-rate translation applied to accrued taxes without the corresponding election, producing figures that cannot be tied to any published rate table.

Bringing it together

The paid-versus-accrued question looks like a technicality on a form and behaves like a structural decision about your entire compliance history. For a taxpayer coming forward voluntarily after several unfiled years, it is made once, at the front of the process, with consequences that run through every year of the catch-up and every year afterwards. Getting it right is worth real money; getting it wrong is not correctable by amendment. Further reading across our cross-border guides covers the surrounding mechanics, from FBAR exposure to treaty resourcing.

If you are catching up on unfiled US returns from the UK, or you have inherited a filing history where the basis was never consciously chosen, we can model both outcomes across your full horizon before anything is committed. Please contact our cross-border team for a confidential consultation. We will review your UK payment history, your carryover position and your planned events, and set the election deliberately — once, correctly, and with the documentation to stand behind it.