Roth abroad: the one US wrapper that survives relocation

An American stays a US taxpayer wherever they live, and on relocating usually loses almost the entire local tax toolkit: deductions and reliefs are tied to US federal tax and do not fire across someone else's border. Against that background the Roth stands out — handled carefully, its tax-free status can survive a change of residence. For a wealthy family the stake is measured in decades of untaxed growth, which is why a separate discipline builds up around the Roth: which treaties recognise it, and how not to lose the relief on the way in.

Concept

A Roth IRA is §408A of the Internal Revenue Code: already-taxed money is contributed, and from there the account grows and qualified distributions are not taxed in the US at all. The tax on this money is paid once, on the way in, and never again — not on the growth, not on the way out.

What makes the Roth genuinely rare is that it can survive a move out of the US. Almost every US tax break is tied to US tax and falls apart abroad. The Roth is the exception — but only where a tax treaty expressly props the exemption up: in the United Kingdom that is Article 17 of the US-UK income tax treaty; in Canada it is a separate election. Where there is no such support, the relief hangs in mid-air.

What follows: how this works country by country, where the Roth breaks on the way in (the FEIE versus the contribution room), and why the aggressive «Thiel play» with founder shares runs into §4975. The legal anchors: IRC §408A, Article 17 of the US-UK treaty, Article XVIII(7) of the Canada-US treaty, and IRC §4975.

Key parameters of the topic:

How a Roth works, and why it is unusual

Inside the US the picture is simple: post-tax money is contributed, a qualified distribution (after age 59½ and once the five-year rule is met) carries zero federal tax, and there are no required minimum distributions during the owner's lifetime. This relief cannot be «credited» against anyone else's tax, because there is nothing to credit — the US tax here is zero by definition.

Why the Roth, of all wrappers, survives relocation

Compare it with QSBS under §1202 or the preferential long-term capital gains rate: those are deductions from US tax, and the moment a person becomes tax-resident somewhere else, the local system taxes the gain on its own terms with nothing to credit against it. The Roth works the other way round. Its qualified distribution is already exempt in the source state (the US), and a well-drafted treaty obliges the residence state to mirror that exemption rather than tax the payment afresh.

The United Kingdom: Article 17 and why the relief held in 2025

The UK treaty explanation expressly uses Roth IRA distributions to illustrate Article 17(1)(b)'s mirror exemption. A payment must fall within that provision and satisfy its conditions. Lump sums require separate classification under Article 17(2) and the saving clause. UK treatment is substantiated through UK filing rules; Form 8833 discloses a reportable treaty-based US return position, rather than claiming relief from HMRC.

HMRC's lump-sum guidance explains that Article 17(2) does not prevent the residence state from taxing under Article 1(4). Article 17(1)(b) has a saving-clause exception, but it is unsafe to assume every Roth withdrawal falls under it. Establish whether the proposed payment is a covered distribution or a lump sum, then apply the relevant treaty provision and UK domestic law. This does not itself establish that a particular Roth lump sum is taxable.

Canada: a one-⁠time election and a ban on contributions

The CRA's Roth guidance distinguishes two benefits: an Article XVIII(7) election defers tax on accrued, undistributed income, while XVIII(1) can exempt a distribution that would be tax-free in the US and retains pension status. The election is one-time and irrevocable for each account, generally due with the return for the year Canadian residence begins. After a first Canadian Contribution, all subsequently accrued income loses the deferral; the protected distribution amount is limited to the balance immediately before that contribution. Qualifying Roth-to-Roth and Roth 401(k) rollovers are excluded from Canadian Contributions; a traditional IRA conversion is included.

France: why «treaty-specific» is not a figure of speech

France is the counter-example. There is an argument for exemption: under Article 18 of the US-France treaty, distributions from US retirement accounts can be treated as taxable only in the US, and the Roth is brought under that heading. But the French tax authority does not recognise the Roth's tax-free status automatically — the position is not guaranteed, needs documentary support, and if the authority decides the provision does not apply in the holder's case, the distribution lands in the French base. So the UK and Canada offer a workable path, while France is a grey zone that cannot be treated as a given. And in any event the Roth account is reportable: Form 3916 in France, FBAR and Form 8938 in the US.

Australia is a harsher illustration still. Its tax treaty with the US recognises the familiar retirement accounts (traditional IRA, 401(k)), but the Roth does not fall under the treaty, and the ATO does not distinguish it from an ordinary IRA. As a result both the growth and the distributions of a Roth land in the Australian tax base and, given the US tax already paid on the way in, the account risks being taxed twice. The same account by form stays exempt in the UK and Canada and is taxed in Australia; the whole difference lies in the text of the particular treaty.

Getting in: the FEIE versus the contribution room

This is the subtlety that trips up half of all Americans abroad. Putting money into a Roth at all requires «taxable compensation» — earned income that stays in the US tax base. If all earnings are excluded through the Foreign Earned Income Exclusion (Form 2555), no compensation is left, and the contribution room disappears or is cut back.

The fix is the method chosen: tax is computed through the Foreign Tax Credit (Form 1116) instead of the FEIE — then the income stays in the US base as compensation, and the contribution right survives (within the Roth MAGI limits). The alternative is to exclude only part of the income under the FEIE. Keep in mind that this is the contribution layer; the treaty protection of distributions discussed above is a separate matter.

The «Thiel play»: where the Roth breaks on §4975

The most cited case: a founder puts his own founder shares into a self-directed Roth while they are worth pennies, and all the multi-billion-dollar growth that follows comes out untaxed. It can be repeated, but the corridor is narrow, and it has two walls.

The first is §4975 prohibited transactions: direct or indirect dealings between the IRA and a «disqualified person», and any use of the account's assets for the personal benefit of the owner, are barred. The crucial threshold: if the Roth owner together with related persons holds 50% or more of the company, the company itself becomes a disqualified person and the account can no longer invest in it. Thiel's stake in PayPal was below 50%, so the company was not disqualified — and that is not a detail but the central condition of the whole structure.

Twelve Treaties on One Grid

Behind the four countries above stand four different treaty designs, and the same designs repeat across the US network. What decides the Roth's fate is one clause: whether the residence state must exempt a pension payment to the extent the source state would exempt it. Read against the treaty texts published by the IRS, the network splits into three groups.

The first group is the mirror clause. The UK, Belgian and Maltese treaties use the same wording in Article 17(1)(b), and each lists that subparagraph among the exceptions to the saving clause in Article 1(5)(a). The US Treasury's Technical Explanations for the UK, Belgium and Malta each expressly use a Roth IRA distribution as an example of the mirror exemption: a distribution from a US Roth IRA to a resident «would be exempt from tax» in that state to the same extent it would be exempt in the United States (the Belgian and Maltese explanations). Canada separates its distribution exemption from the election for deferral of accrued income, and France by giving the source state the exclusive right to tax pension distributions under the Article 18 inserted by the 2004 Protocol, which leaves only the question of whether a Roth is a pension arrangement at all.

The second group is the classic residence-only article with no mirror: Germany, Ireland, Italy, Spain, Switzerland, Japan and Australia. There the treaty hands the pension to the residence state and says nothing about the source state's exemption, so the Roth's fate is set by domestic law, and domestic law generally has no concept of a post-tax account whose growth is never taxed. Germany is the clearest case, because its 2006 Protocol names the Roth: paragraph 16 of the Protocol lists Roth IRAs among US pension plans for Article 18A, then excludes Roth IRAs from equivalence for the contribution-relief provisions of Article 18A(3)(b) and (5)(d). That exclusion alone does not determine distribution tax. Australia narrows the article further by defining pensions as periodic payments, which leaves a lump-sum withdrawal outside it.

The practical reading is that a Roth is portable to exactly four treaty partners on this grid without argument — the UK, Belgium, Malta and Canada, the last on condition of the election — while France is arguable and the other seven require a domestic-law analysis before the move rather than after it. The broader treatment of US and UK pension wrappers on relocation is in pension assets on relocation.

Where it fits

The practical point is for an American planning a move who wants the Roth to stay useful afterwards. Before leaving, it makes sense to fill the Roth as much as possible, including through traditional → Roth conversions, while the person is still inside the US system. Living abroad, compute tax through the FTC rather than the FEIE so as not to lose the contribution right. Moving to Canada, file the election in time and never contribute again. And in choosing between jurisdictions, understand that the UK, Belgium, Malta and Canada give a workable treaty footing, whereas France is arguable and the residence-only treaties in the grid above leave the answer to domestic law.

Risks

A separate layer is aggressive structuring. The «Thiel play» breaks not on a tax rate but on §4975 (self-dealing, the 50% threshold) and on the requirement to buy non-public shares at fair market value: under-pricing the «entry» is the IRS's prime target. Add the political backdrop: very large mega-Roths have been in the crosshairs for years — caps were proposed both in Build Back Better and in Senate Finance initiatives — but these are proposed measures, not enacted law; what one should price in is simply that the rules may tighten. And remember expatriation: giving up US citizenship triggers its own regime (§877A), which the Roth does not switch off.