UK Non-Dom Abolition Tax Planning for Americans (2026)

The UK non-dom regime is gone. From 6 April 2025 the remittance basis was abolished and replaced by the four-year Foreign Income and Gains (FIG) regime, and inheritance tax shifted from a domicile test to a residence test. For US-connected high-net-worth residents, this is the single biggest realignment of UK-US planning in a generation — and the most valuable transitional reliefs expire on a fixed clock.

This guide sets out what has actually changed, why the American dimension makes it harder rather than easier, and the concrete steps sophisticated residents should be taking now. It is written for people whose affairs span both sides of the Atlantic — founders, executives, fund principals and multi-generational families — where a UK decision made in isolation can create an unnecessary US liability, and vice versa.

What exactly replaced the remittance basis?

For two centuries, non-domiciled UK residents could elect the remittance basis: foreign income and gains left offshore escaped UK tax until brought (remitted) to the UK. That is finished. In its place sit three moving parts that every US-connected resident must understand.

The four-year FIG regime

New arrivers who have been non-UK resident for the previous ten consecutive tax years can claim 100% relief on their foreign income and gains during their first four years of UK residence. Unlike the old remittance basis, qualifying funds can be brought into the UK freely during that window without triggering a further UK charge. After four years, the individual is taxed on worldwide income and gains like any other UK resident. The regime is generous but short, and the ten-year prior-non-residence condition means it is genuinely aimed at new and returning arrivers rather than the long-settled.

The Temporary Repatriation Facility (TRF)

Former remittance-basis users are sitting on pools of foreign income and gains that accumulated under the old rules and would historically have been taxed at full rates on remittance. The TRF offers a time-limited window to designate and remit those pre-6 April 2025 funds at a reduced flat rate. The facility is available only for a fixed set of tax years and then closes; after it ends, those offshore funds revert to normal remittance taxation. For anyone with meaningful clean-capital and mixed-fund accounts offshore, the TRF is often the highest-value decision of the entire reform — and the one with the hardest deadline.

Residence-based inheritance tax

Domicile no longer governs UK inheritance tax. From 6 April 2025 a “long-term resident” — broadly, someone UK resident for at least ten of the previous twenty tax years — is within the scope of UK IHT on their worldwide estate. Crucially, exposure does not end the day you leave: an IHT “tail” keeps former long-term residents within scope for a trailing period after departure. For US citizens, this collides directly with US estate tax and makes the US-UK estate and gift tax treaty central to any structuring.

Why the American dimension changes everything

The uncomfortable truth for US-connected residents is that the FIG regime was designed for people who only answer to HMRC. American citizens and Green Card holders never leave the US tax net: the United States taxes its citizens on worldwide income and gains wherever they live. That single fact inverts much of the apparent benefit of the reforms.

Consider the mechanics. Under FIG, the UK exempts your foreign income and gains for four years. Ordinarily, US tax on that same income would be reduced by foreign tax credits for UK tax paid. But if the UK is charging nothing, there is no UK tax to credit — so the US becomes the residual taxpayer and collects in full. The relief that looks so attractive to a non-American can, for a US citizen, simply shift the revenue from London to Washington rather than reduce the overall bill. Our cross-border tax planning team models exactly this interaction before any election is made.

The TRF raises a subtler question. The reduced UK charge on repatriated funds is a UK tax, but whether and how it interacts with the US foreign tax credit system — and against which category of US income — requires careful analysis. A remittance decision that is clearly correct for a British non-dom may produce an uncredited UK cost, a US timing mismatch, or both, for an American. These are precisely the judgement calls our US-UK tax accountants exist to make.

UK versus US treatment at a glance

The trust problem: protection has gone

Before the reforms, offshore trusts settled by non-doms enjoyed “protected settlement” status: foreign income and gains rolling up inside the trust were generally not taxed on the UK-resident settlor until benefits were taken. That protection was largely swept away from 6 April 2025. Many UK-resident settlors of offshore trusts can now be taxed on trust income and gains as they arise, and the IHT status of trust property is recalculated by reference to the settlor’s long-term residence rather than their domicile.

For US-connected families the trust position is doubly fraught. A structure built to be efficient under UK non-dom rules may already have been a US foreign grantor or non-grantor trust with its own reporting obligations — Forms 3520 and 3520-A, throwback tax on accumulated distributions, and PFIC exposure on underlying funds. Redesigning these vehicles now requires a single team looking through both lenses at once. Our trusts and estate planning specialists routinely unwind or restructure legacy settlements so they do not become tax traps on either side of the Atlantic.

What should US-connected HNWIs do now?

The reforms reward those who act inside the transitional windows and penalise those who wait. The following priorities apply to most sophisticated US-connected residents, though the right sequence depends entirely on individual facts.

• Map every account, entity and fund pool. Before any election, you need a precise picture of clean capital, mixed funds, offshore income and gains, and trust interests — segregated by date relative to 6 April 2025. This diagnostic drives every subsequent decision.
• Model the TRF against the US foreign tax credit. Decide which offshore funds to designate and remit while the reduced rate is available, and confirm how the UK charge lands in your US position. This is a use-it-or-lose-it window.
• Test FIG eligibility and its real value to you. Confirm the ten-year prior-non-residence condition and quantify whether the UK exemption genuinely reduces your combined bill or merely shifts it to the IRS.
• Reassess CGT disposal timing. Former remittance-basis users may be able to rebase qualifying foreign assets to a historic value for UK CGT. Because the US taxes gains from original cost regardless, disposal timing must be optimised across both systems.
• Restructure or unwind exposed trusts. Legacy protected settlements should be reviewed against both the new UK rules and existing US foreign-trust treatment before distributions or wind-ups are triggered.
• Refresh estate planning for residence-based IHT. Recalculate worldwide IHT exposure, factor in the departure tail, and align wills and structures with the US-UK estate tax treaty.
• Confirm your US compliance is current. The UK reforms are a natural moment to verify that US returns, FBARs and Form 8938 are up to date. If they are not, the IRS streamlined filing route may allow a penalty-free catch-up before any restructuring begins.

Clean capital, mixed funds and the remittance legacy

One of the least understood consequences of the reform is what happens to the offshore account structures that non-doms spent years carefully segregating. Under the old rules, a disciplined non-dom kept clean capital (funds that could be remitted tax-free) separate from income and gains accounts, so that money could be brought to the UK without triggering a charge. That architecture does not simply disappear on 6 April 2025 — the historic character of each pool still matters when you decide what to remit and when.

The TRF is, in effect, an amnesty on the untaxed layers of those accounts: it lets you designate previously untaxed foreign income and gains and pay a reduced flat charge, after which the funds become freely remittable. But the decision of which pools to designate, in which order, and how the designation is reported on your US return is genuinely intricate. A US citizen who designates and remits in the wrong sequence can create a UK charge that earns no US credit, or a US income event with no matching UK relief. Getting the ordering right — and documenting the analysis contemporaneously — is where real value is preserved. Our private client and high-net-worth advisers build this remittance map before a single transfer is made.

Inheritance tax, US estate tax and the treaty

For US citizens, the shift to residence-based IHT is not just a UK story; it is a collision of two of the highest death-tax regimes in the world. Once you are a UK long-term resident, your worldwide estate is exposed to UK inheritance tax. As a US citizen, that same worldwide estate is also within US estate tax. Without careful planning, the same asset could be taxed twice.

The US-UK estate and gift tax treaty is the primary defence, allocating taxing rights and providing credits so that the two systems dovetail rather than stack. But the treaty does not run itself: which country has primary taxing rights over a given asset depends on situs, residence and the nature of the property, and the interaction with lifetime gifting, spousal transfers and trust property is far from mechanical. The residence-based regime also introduces the departure tail, meaning a family that relocates away from the UK can remain within UK IHT for a period of years afterwards — a fact that must be built into any exit plan. Coordinating all of this is core to our trusts and estate planning work for transatlantic families.

Overseas Workday Relief and inbound executives

US executives relocating to the UK should note that Overseas Workday Relief (OWR) survived the reforms but was reformed and re-linked to FIG eligibility. It now typically covers the same four-year window and is subject to a cap based on the lower of a percentage of qualifying employment income or an annual monetary limit. For an American, OWR reduces the UK charge on the non-UK duties portion of employment income — but the US still taxes the whole amount, so the relief again risks simply reallocating tax rather than eliminating it. Structuring cash bonuses, equity vesting and workday tracking demands genuinely bilateral advice; our private client and high-net-worth team builds these arrangements for inbound principals and C-suite arrivers.

The cost of waiting

Every element of the reform package that helps you is time-limited, and every element that costs you is permanent. The TRF closes after the 2027/28 tax year. CGT rebasing applies to disposals from a fixed date. The four-year FIG window is set by your arrival and cannot be extended. Residence-based IHT, by contrast, tightens quietly each year you remain, and the departure tail means you cannot simply leave to reset the clock. For most US-connected residents the genuine planning window is now measured in months.

The families who will look back on these reforms with equanimity are those who treated 2025 to 2028 as a structured project: diagnose, model both tax systems together, execute inside the windows, and document everything. The ones who will regret it are those who assumed a UK relief was an unqualified win without ever checking the US side of the ledger.

Speak to a cross-border specialist

The abolition of non-dom status has not simplified UK-US planning — it has raised the stakes and shortened the deadlines. Whether the FIG regime, the TRF, CGT rebasing or trust restructuring is right for you depends on the interaction of two tax systems that were never designed to cooperate, and on windows that are already open. If you are a US citizen, Green Card holder or US-connected family resident in the UK, now is the moment to have your position modelled across both jurisdictions by advisers who work in both. Arrange a confidential consultation with Jungle Tax to protect your wealth before the transitional reliefs expire.