Missed Reporting Pension Account: Unreported Treaty Claim

If a UK employer scheme or personal pension was never reported on any US return, the treaty deferral on undistributed growth is usually still available. The benefit flows from the convention itself, not from an election that had to be made on a timely filed return — but it must now be claimed expressly, in writing, inside the catch-up pack.

That single point decides the size of the liability. A missed reporting pension account is often framed as a forms problem — an FBAR here, a Form 8938 there. It is not. The forms carry penalty exposure; the treaty claim carries the tax. For a six-figure SIPP that has compounded through a decade of unfiled years, the difference between a sustained treaty position and a failed one is the difference between a nil-tax submission and one carrying tax, interest and a PFIC computation on every fund inside the wrapper. This guide, from Jungle Tax, sets out whether the claim survives the years of silence, and exactly what goes into the disclosure so that it stands.

Does a treaty claim survive when no return was ever filed?

This is the question every generalist page skips, and it has a defensible answer.

US tax law distinguishes sharply between a benefit conferred by treaty and an election created by the Internal Revenue Code. Code elections frequently carry hard timing conditions — make it late and you have lost it, absent relief. A treaty benefit is different in kind. The convention allocates taxing rights between two sovereigns; it does not condition the allocation on the taxpayer having filed a US return by a particular date.

What the Code does impose is a disclosure obligation. Section 6114 requires a taxpayer who takes a return position that a treaty overrules or modifies an internal revenue law to disclose that position, and section 6712 attaches a fixed penalty per failure. Read carefully, that is a reporting rule with its own penalty — not a rule that extinguishes the underlying entitlement. The IRS position on Form 8833 is set out on its own guidance page for Form 8833, Treaty-Based Return Position Disclosure, and it is framed throughout as a disclosure requirement.

The practical consequence for a dual filer with an unreported pension is this: you are not time-barred from the deferral. You are, however, making a claim without the evidential comfort of contemporaneous filings, into a submission that the IRS will read as a whole. The claim must therefore be made loudly, consistently across every year in the pack, and with the scheme documentation behind it.

Where the argument is genuinely weaker

Two situations deserve candour. First, where the position depends not on the treaty allocating a taxing right but on a Code election with its own deadline — the classic example being a mark-to-market or qualified electing fund election for a collective fund — lateness bites in the ordinary way. Second, where conduct across the unfiled years suggests the position is being constructed retrospectively rather than asserted, the whole submission is weakened, including the non-willfulness certification. Consistency of story matters more here than in almost any other area of catch-up work.

Which treaty article actually defers the tax on the growth?

Precision matters, because the competing pages routinely cite the wrong article.

• The article dealing with pension distributions governs how a payment out of the scheme is taxed once it is made, and which country gets to tax it.
• The article dealing with pension schemes contains the paragraph that matters here: income earned by the pension scheme may be taxed as income of the individual member only when it is distributed. That is the deferral on undistributed growth.
• A further paragraph in the same article deals with the deductibility of employee and employer contributions, subject to a cap by reference to the corresponding US plan limit.

Confusing the distribution article with the scheme article is not a semantic error. A disclosure statement that cites the distribution provision to justify deferral of accumulation-phase growth is claiming the wrong thing, and an examiner who reads it carefully will say so. The current consolidated text is published by HMRC on the UK/USA double taxation convention page on GOV.UK, and the article and paragraph references in your statement should be checked against it for the years being filed.

The saving clause, and why the deferral survives it

The saving clause permits each state to tax its own citizens and residents as though the treaty had not been concluded. Taken alone, it would neutralise the deferral for every US citizen in the UK — which is exactly the misconception that leads some advisers to tell clients the treaty is useless to them.

It does not, because the saving clause is expressly made subject to a list of carved-out provisions, and the pension scheme paragraph that defers tax on undistributed income sits within that list. That structural point is the load-bearing sentence in the whole disclosure statement, and it should appear in the statement in terms: the position is taken under the specified paragraph, which is excepted from the saving clause by the enumerated carve-out, and therefore applies notwithstanding the member's US citizenship.

What actually breaks if the claim fails

Clients underestimate this. If the deferral is not available or is not properly claimed, the analysis reverts to domestic US principles, and a funded foreign retirement arrangement over which the member has control is commonly analysed as a foreign grantor trust. Three consequences follow at once.

• Current taxation of inside build-up. Dividends, interest and realised capital gains inside the wrapper become taxable to you annually, in the year they arise, on returns you are now filing several years late.
• PFIC exposure on the holdings. UK-domiciled collective funds — OEICs, unit trusts, investment trusts — held inside a personal pension can fall to be tested as passive foreign investment companies once the wrapper is looked through. The excess distribution regime then applies with its deferred-interest charge, and no timely mark-to-market or qualifying election is available.
• Foreign tax credit mismatch. The UK taxes nothing during accumulation and taxes the pension on drawdown. If the US taxes the growth now and the UK taxes the same economic value in fifteen years, the credits arise in the wrong periods and are largely wasted.

That third point is why this is a cross-border question and not a US one. A US-only preparer will compute the inside build-up and move on. The compounding cost lands in the UK, decades later, and is irrecoverable.

US versus UK treatment: where the two systems diverge

Point in the pension life cycle	US treatment for a dual filer	UK treatment (HMRC)
Employee contributions	Not deductible under domestic law; relief available under the treaty contribution paragraph, capped by reference to the US plan limit	Relief at marginal rate through net pay or relief at source, subject to the annual allowance
Employer contributions	Potentially includible in income under domestic law; treaty paragraph is designed to prevent that outcome	Not a taxable benefit in kind; deductible for the employer
Growth inside the scheme	Deferred under the treaty scheme paragraph; taxable annually as grantor trust income if the claim fails	No tax during accumulation
Collective funds held inside	Potential PFIC testing if the wrapper is looked through; irrelevant if the deferral holds	No equivalent regime
Pension commencement lump sum	Contested; the exclusion is a treaty position that must be disclosed, and interacts with the saving clause differently from the growth paragraph	Tax-free up to the applicable lump sum allowance
Ongoing drawdown	Taxable, with credit for UK tax under the credit article	Taxable at marginal rates via PAYE
Account reporting	FBAR and Form 8938 where thresholds are met; trust reporting subject to the retirement trust exemption	No equivalent taxpayer reporting; scheme reports under FATCA/CRS

What goes into the disclosure statement

A one-line entry saying "treaty applies" is worthless. The statement that survives review does five things.

1. Identifies the scheme precisely

Name of the scheme, HMRC registration status, whether it is an occupational scheme or a personal pension, the provider, the member's date of joining, and the account or policy reference. A treaty claim is scheme-specific; a generic paragraph covering "my UK pensions" invites the examiner to ask which one.

2. States the exact provision relied on

Article, paragraph and subparagraph, plus the carve-out reference that takes the paragraph outside the saving clause. Cite the convention as amended by the protocol, and cite the same reference identically in every year of the pack.

3. Identifies the domestic law being overridden

Name the Code provisions that would otherwise apply — the grantor trust rules and the general inclusion provision — and state that the treaty modifies their operation for the years disclosed. This is what section 6114 is actually asking for, and it is what most late filings omit.

4. Quantifies what has been excluded

State the undistributed scheme income excluded from gross income for each year, or state that it is not reasonably determinable and explain why (common for older occupational schemes where the provider will not produce member-level income splits). An unquantified claim looks evasive; a quantified one with a stated methodology looks like compliance.

5. Ties into the non-willfulness narrative

The reason the pension was never reported and the reason the treaty position was never disclosed are the same reason, and the narrative in the certification must say so in plain terms. A statement claiming a sophisticated treaty position sitting beside a certification pleading unfamiliarity with US filing obligations reads as contradictory unless the two are drafted together. This is where a specialist US-UK tax accountant earns the fee.

Sequencing the catch-up pack

Because income was omitted, the lighter-touch procedures are off the table. The delinquent information return and delinquent FBAR submission routes both assume all income was properly reported; an unreported pension almost always fails that assumption. The realistic route is the streamlined programme, and the IRS sets out both tracks on its streamlined filing compliance procedures page.

Practical ordering that works:

• Reconstruct the scheme first, not the returns. Obtain annual statements, transaction histories and the scheme rules for every year in scope. The returns cannot be built until you know whether there is measurable inside build-up at all.
• Decide the treaty position before drafting a single return. The position drives the income figures, which drive the tax, which drives whether the submission is nil-tax.
• Prepare all covered years to one methodology. Three years of returns and six years of FBARs is the standard footprint; the treaty statement must be identical in each of the three.
• Draft the certification narrative last, once the numbers and the treaty position are fixed, so that it describes what was actually filed.
• Run the UK position in parallel. If UK returns are also missing or a relief was never claimed, correct both sides together — see our note on UK tax services for the HMRC-side workstream.

Do Forms 3520 and 3520-A apply to the pension?

This is the second-order question, and it is genuinely unsettled. Revenue Procedure 2020-17 created an exemption from the section 6048 trust reporting requirements for certain tax-favoured foreign retirement trusts, provided a set of conditions is met — broadly, that the arrangement is genuinely retirement-focused, tax-favoured in its home country, subject to information reporting, and contribution-limited.

Whether a given UK arrangement satisfies every condition is a document-level question, and a self-invested personal pension with wide investment freedom and no employer involvement will not always fit as comfortably as a straightforward occupational scheme. Two things are certain: relief from the trust forms does not remove FBAR, Form 8938 or the underlying income analysis, and relief is only relevant at all if the treaty deferral has failed or is in doubt.

FBAR and Form 8938 on a pension that was never reported

A funded UK pension in which the member has a determinable beneficial interest — a personal pension or a defined contribution occupational scheme — is generally a reportable foreign financial account for FBAR, and a specified foreign financial asset for FATCA reporting, in each case once the applicable thresholds are met on an aggregate basis with every other foreign account. An unfunded promise from an employer under a final salary scheme sits differently, and the answer turns on the scheme rules rather than on a rule of thumb.

Two practical notes. First, the FBAR threshold is an aggregate one and is easily crossed by a modest pension sitting alongside a current account and an ISA — see our guidance on catching up through the streamlined programme for how the years knit together. Second, the values used for FBAR and for Form 8938 are not always the same figure, and a submission that uses one number for both attracts questions it does not need.

Does an unreported pension keep the assessment period open?

Yes, and this is the argument for filing even where the treaty claim means no tax is due. Where a required international information return has not been filed, the assessment period for the return as a whole can remain open — not merely for the item omitted, but for everything on that return — until a period after the missing return is finally filed. Years you assume are closed may not be closed at all. Filing the pack is what starts the clock, and doing so voluntarily is materially better than doing so after contact.

A worked illustration

Consider a UK-resident US citizen who joined a UK employer's defined contribution scheme on arrival and later consolidated into a SIPP, never having filed a US return. The account is now materially into six figures, roughly half of which is investment growth, held in a handful of UK-domiciled funds.

With the treaty claim sustained: the undistributed growth is excluded from gross income in each covered year. Contributions are addressed under the contribution paragraph. The funds inside the wrapper are not looked through, so no PFIC computation arises. The submission is likely to be nil-tax or close to it, with the exposure concentrated in reporting-form risk that the programme is designed to resolve.

With the treaty claim failing: the scheme is analysed as a grantor trust, the annual inside build-up is taxable, each UK fund is tested as a PFIC, and the excess distribution regime applies with its interest charge across the whole holding period. The tax and interest can run to a multiple of anything the reporting penalties would have produced — and the mismatch means the UK tax paid on eventual drawdown will largely fail to relieve it. Our note on cross-border tax positioning sets out how the two systems' timing differences compound.

The five errors we see most often

• Citing the distribution article to defer accumulation growth. The wrong provision, claimed confidently, is worse than a general statement.
• Claiming the treaty in one year of the pack and not the others. Inconsistency across three returns is the single easiest thing for a reviewer to spot.
• Ignoring the saving clause entirely. A statement that does not address it looks as though the preparer did not know it existed.
• Reporting the account and stopping. An FBAR and a Form 8938 disclose the existence of the pension without resolving how its income is taxed. Reporting is not a position.
• Writing the certification narrative before the technical work is finished. The narrative must describe the return that was actually filed, not the one that was originally imagined.

Speak to us before you file

A pension that was never reported is recoverable, and in most cases recoverable at little or no US tax cost — but only if the treaty position is identified, drafted and evidenced before the returns are built rather than bolted on afterwards. We prepare these submissions for founders, executives and internationally mobile families for whom the pension is a significant asset and a failed claim would be expensive for decades. If a UK employer scheme or personal pension has never appeared on a US return, contact our cross-border team for a confidential consultation. We will assess the scheme documentation, tell you candidly how strong the treaty position is, and set out the route to full compliance before the IRS or HMRC reaches you first.