How should the UK tax people who've recently arrived from abroad?
The UK abolished 225-year-old "non-dom" status from April 2025. What should replace it was genuinely contested beforehand, and TPA's own 2022 reform proposal is a useful way to see the trade-off clearly, set against what the government actually did. No winner declared here.
The problem
Every country that wants to attract internationally mobile talent, investors and entrepreneurs faces the same design question: should someone who has just arrived, and might leave again, be taxed on their worldwide income and gains from day one — or does a temporary, preferential regime attract people (and their eventual permanent tax contribution) who would otherwise never come at all? Too generous, and long-term residents who should be paying full UK tax structure their affairs to stay "temporary" indefinitely — the UK's old domicile-based non-dom regime, which could in principle apply for 15 years, was widely criticised on exactly this basis. Too strict, and the UK becomes less attractive than competitor financial centres for the specific population — high earners, entrepreneurs, investors — whose decision to come is genuinely price-sensitive to how they will be taxed.
- ModelledExternal academic estimate (Advani, Burgherr & Summers) that full abolition of non-dom status would raise "at least £3.2bn" in income tax and CGT — the external study TPA's own £2bn figure discounts down from, not a TPA-original estimate. — Advani, A., Burgherr, D. & Summers, A., "Taxation and Migration by the Super-Rich" (IZA Discussion Paper No. 16432)
- ObservedTPA's own proposed lifetime cap on preferential treatment: £2m of foreign income/gains, within a shortened 3-year window (versus the old regime's up-to-15-year window). — Neidle, D., "The non-dom rules: how to raise £2bn more tax, and make the UK more competitive" (Tax Policy Associates)
- ObservedThe regime the government actually introduced from April 2025: a 4-year 100% exemption on foreign income and gains for new arrivals (the "FIG regime"), with full UK Inheritance Tax exposure after 10 years of UK residence — no £2m cap in the form TPA proposed. — HM Revenue & Customs / HM Treasury, "Reforming the taxation of non-UK domiciled individuals" (policy paper and guidance)
The live debate this maps onto
TPA's 2022 proposal
Dan Neidle proposed replacing the domicile concept entirely with a statutory "temporary non-resident" scheme: shorten the preferential window from up to 15 years to 3 years; cap the foreign income/gains exempted at £2m over a lifetime; extend the same temporary-residence logic to Inheritance Tax (exempting temporary non-residents' foreign assets during the window, not just income tax); and close the offshore-trust loophole by taxing trusts annually (5% of assets) or treating them as if the settlor still owned the underlying property directly. The framing was explicitly about simplicity and certainty, not generosity: "End the 'domicile' concept, which is complex and uncertain — and with all things complex and uncertain, that makes life harder for honest taxpayers and easier for tax avoiders."
Source: Neidle, D., "The non-dom rules: how to raise £2bn more tax, and make the UK more competitive" (Tax Policy Associates) — 27 September 2022
What the government actually did (from April 2025)
The remittance basis was abolished and replaced with a residence-based regime: new arrivals get a 4-year 100% exemption on foreign income and gains (the "FIG regime"), a materially more generous headline exemption than TPA's proposed £2m lifetime cap, but a much shorter window (4 years vs TPA's 3-year window plus the £2m cap could in principle run longer for smaller amounts). Foreign assets become fully exposed to UK Inheritance Tax after 10 years of UK residence, and the trust-protection loophole TPA specifically flagged in 2022 was closed as part of the same reform.
Source: HM Revenue & Customs / HM Treasury, "Reforming the taxation of non-UK domiciled individuals" (policy paper and guidance) — 2024, effective 6 April 2025
TPA's own assessment of the actual reform
In a 2024 follow-up, TPA engaged directly with claims (from an industry-funded Oxford Economics survey) that the government's reform would cost the UK £1bn in lost revenue through departures — and rebutted them, defending the reform's direction. The piece does not explicitly benchmark the final policy against TPA's own 2022 proposal parameter-by-parameter; its substantive focus is debunking the £1bn claim, not reconciling old proposal against new law.
Source: Neidle, D., "Will Labour's non-dom reforms cost the UK £1bn?" (Tax Policy Associates) — 8 September 2024
The real design options
Every option here is a genuine choice a policymaker could actually make. Each has real, sourced trade-offs — none is presented as the answer.
TPA's 2022 proposal: 3-year window, £2m lifetime cap, extend to IHT
Replace domicile with a statutory temporary-residence scheme: 3 years of preferential treatment, capped at £2m of foreign income/gains over a lifetime, the same logic extended to Inheritance Tax, and the offshore-trust loophole closed.
Pros
- InferredA lifetime cap directly targets the "temporary in name only" avoidance TPA identified as the old regime's central flaw — someone cannot simply keep re-qualifying indefinitely. — Neidle, D., "The non-dom rules: how to raise £2bn more tax, and make the UK more competitive" (Tax Policy Associates)
- InferredExtending the same logic to IHT closes a gap the actual 2025 reform also independently identified and closed (the trust loophole) — two independent design processes converging on the same fix is a modest corroborating signal.
Cons
- InferredA £2m lifetime cap is more restrictive than what the government ultimately judged competitive enough to enact — the actual 4-year 100% exemption has no equivalent cap, suggesting the government weighed the competitiveness risk of a cap more heavily than TPA's proposal did. — HM Revenue & Customs / HM Treasury, "Reforming the taxation of non-UK domiciled individuals" (policy paper and guidance)
- UncertainThe £2bn revenue estimate this proposal cites is a discount TPA itself applied to an external academic paper's £3.2bn full-abolition estimate — a plausible but not independently TPA-verified extrapolation. — Advani, A., Burgherr, D. & Summers, A., "Taxation and Migration by the Super-Rich" (IZA Discussion Paper No. 16432)
The regime actually introduced (April 2025): 4-year 100% exemption, full IHT after 10 years
A residence-based regime: full exemption on foreign income/gains for new arrivals' first 4 years, no lifetime £ cap, full UK Inheritance Tax exposure on worldwide assets after 10 years' UK residence.
Pros
- InferredA shorter, simpler time-window (4 years, no cap to track) may be easier for HMRC to administer than a lifetime running total across a taxpayer's whole life.
- ObservedTPA's own 2024 assessment defended the reform's revenue case against an industry-funded claim that it would cost the UK £1bn — a broadly supportive, though not uncritical, external read on the policy actually chosen. — Neidle, D., "Will Labour's non-dom reforms cost the UK £1bn?" (Tax Policy Associates)
Cons
- InferredA 100%, uncapped exemption for the first 4 years is, for a very high earner arriving with substantial foreign income, more generous than TPA's proposed £2m cap — the competitiveness-vs-avoidance trade-off was resolved more toward competitiveness than TPA's own proposal argued for. — Neidle, D., "The non-dom rules: how to raise £2bn more tax, and make the UK more competitive" (Tax Policy Associates)
- UncertainA hard 4-year cliff-edge (rather than a tapered or capped approach) could itself distort behaviour around year 4 specifically — a design risk neither TPA's 2022 piece nor its 2024 follow-up directly quantifies.
No special regime: full worldwide taxation from day one of residence
The simplest option — anyone who becomes UK tax-resident is taxed on worldwide income and gains immediately, with no preferential transition period at all.
Pros
- InferredMaximally simple to administer and horizontally fair — a new arrival and a lifelong UK resident with identical income are taxed identically from day one.
- InferredRemoves any "temporary means never really temporary" avoidance risk entirely, since there is no preferential window to extend or game.
Cons
- InferredNeither TPA's proposal nor the government's actual reform chose this option — both judged some transitional relief necessary for competitiveness, which is itself a relevant (though not conclusive) signal about how the trade-off was weighed by two independent processes.
- UncertainNo UK-specific quantified estimate of this option's own effect on inbound migration of high earners/investors was found in this research pass — its competitiveness cost, specifically, is asserted by proponents of a transitional regime rather than separately measured.
What real precedents show
Presented as evidence to weigh, not as an endorsement of any one path.
The old domicile-based regime it replaced
The pre-2025 regime allowed non-domiciled UK residents to elect the "remittance basis" — paying UK tax only on foreign income/gains actually brought into the UK — for up to 15 years of UK residence, a materially longer and less-capped preferential period than either TPA's 3-year/£2m proposal or the actual 4-year FIG regime that replaced it.
Source: HM Revenue & Customs / HM Treasury, "Reforming the taxation of non-UK domiciled individuals" (policy paper and guidance) — 2024, effective 6 April 2025
Who actually bears this — not one group
The population actually affected by any version of this design question is narrow and specific — internationally mobile high earners, investors and entrepreneurs choosing where to be tax-resident — not UK residents generally.
| Group | Their exposure |
|---|---|
| New arrivals with substantial foreign income or gains | Directly affected by exactly how generous and how long any transitional exemption is — this is the population the whole design question is actually about. |
| Long-term UK residents born or long-settled in the UK | Not affected by any version of this regime — none of the three options changes how someone who has never claimed non-dom-style treatment is taxed. |
| The Exchequer | Faces a genuine trade-off between the revenue a more generous regime forgoes from those who would have come and paid full UK tax on everything anyway, versus the revenue a stricter regime risks losing if genuinely mobile high earners choose a competitor jurisdiction instead — the empirical size of that second effect is contested across all three options above. |
What’s well-evidenced, and what’s contested
- Well-evidenced
Only people with substantial foreign income or gains, arriving after a period of non-UK residence, are directly affected by any version of this design question.
This follows directly from how every option above is scoped — TPA's proposal, the actual FIG regime, and full worldwide taxation all define eligibility the same way (new arrivals with foreign income/gains); none of them changes the tax treatment of someone who has never claimed non-dom-style relief.
- Contested
A less generous non-dom-style regime would cause a materially damaging exodus of high earners and investors.
TPA's own 2024 piece rebutted one specific version of this claim (an industry-funded £1bn estimate) for the actual reform enacted — but the general question of how price-sensitive this specific population's location choice is remains genuinely disputed across the wider literature, not settled by one rebuttal of one estimate.
Source: Neidle, D., "Will Labour's non-dom reforms cost the UK £1bn?" (Tax Policy Associates)
Last updated 2026-09-15.