Cross-Border Estate Planning for High-Earning US Consultants
Estate planning: high-earning US consultants face two tax systems at once: the US estate tax on their worldwide estate at up to 40%, and the UK inheritance tax at 40% above the nil-rate band. Coordinating the US-UK treaty, trusts, pensions, and business succession helps prevent a lifetime of earnings from being taxed twice on death.
By the Jungle Tax Cross-Border Tax Team — reviewed by a US-UK dual-qualified adviser (CPA / Enrolled Agent).
Why does estate planning matter more for high-earning US consultants abroad?
Because two countries can each claim tax on the same death, the rules moved sharply against long-term residents in April 2025. A US citizen never escapes the US estate tax net wherever they live, and the UK now taxes worldwide assets once someone has been resident long enough. Estate planning for high-earning US consultants has to deliberately reconcile both regimes, because neither country automatically gives credit to the other without the right claims in place.
The consultant profile is distinctive. Income is often high, lumpy, and routed through a personal company; wealth accumulates quickly in retirement accounts, property, and business equity. That concentration is exactly what pushes an estate over both thresholds. Effective planning starts with mapping where every asset sits and which country has taxing rights over it.
Timing compounds the problem. A consultant who sells a business, exercises equity, or realizes a large fee in a single year can spike their taxable estate overnight, and a death in the wrong tax year can strand assets on the wrong side of a threshold. Building the plan early — while there is still room to gift, restructure and insure — is worth far more than reacting once the numbers are fixed.
The two thresholds that matter
On the US side, the One Big Beautiful Bill Act (signed 4 July 2025) set the federal estate and gift tax exclusion at $15 million per person for 2026, up from $13.99 million in 2025, and made it “permanent,” subject to annual inflation indexing. On the UK side, the nil-rate band stays at £325,000 with a £175,000 residence nil-rate band, both frozen until April 2031. A high earner can look comfortably under the US number yet sail well past the UK one.
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Feature
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United States (2026)
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United Kingdom (2025/26)
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Headline death-tax rate
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40%
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40%
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Tax-free amount
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$15,000,000 exclusion
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£325,000 nil-rate band + £175,000 residence nil-rate band
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What is taxed
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Worldwide estate of a US citizen
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Worldwide estate of a long-term UK resident
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Spouse transfers
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Unlimited to a US-citizen spouse
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Unlimited to a UK-domiciled/long-term-resident spouse
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Freeze/indexing
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Indexed to inflation annually
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Frozen to April 2031
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How does the UK’s residence-based inheritance tax reform change the picture?
It replaces domicile with a residence test, so many American consultants will be pulled into UK inheritance tax on their global assets sooner than under the old rules. From 6 April 2025, the concepts of domicile and deemed domicile were abolished for inheritance tax. In its place sits “long-term resident” status.
An individual becomes a long-term UK resident once they have been a UK tax resident for at least 10 of the previous 20 tax years. From that point, their worldwide estate — not just UK assets — is subject to UK inheritance tax. There is also a post-departure “tail”: someone who leaves the UK stays inside the net for between three and ten years, depending on how long they were resident. A consultant who spent a decade in London and then relocated cannot assume they have escaped.
What this means for estate planning for high-earning US consultants
Sound planning now has to track the 10- to 20-year clock carefully. Someone approaching that line has a genuine planning window; someone already past it needs relief through the treaty and lifetime giving instead. For clients still short of long-term-resident status, the years before the clock starts ticking are the most valuable time to restructure.
How do the US-UK treaties stop double taxation?
Two treaties do the heavy lifting: the 1980 US-UK Estate and Gift Tax Treaty and the income tax treaty, backed by foreign tax credits. The estate and gift tax treaty determines which country has primary taxing rights over particular assets and provides credit mechanisms to prevent the same property from being taxed twice. Article-based tie-breakers, a pro rata unified credit for UK-domiciled individuals, and marital deduction relief all flow from it.
Without the treaty, a non-US-domiciled person is exposed to US estate tax on US-situs assets with only a $60,000 exemption — a trap for consultants holding US shares or US real estate. The treaty and careful structuring lift that ceiling. This is where the strategy becomes technical: asset situs, the order of credits, and which return claims the relief all have to line up.
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Instrument
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What it does
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Watch-out
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US-UK Estate & Gift Tax Treaty (1980)
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Allocates taxing rights; pro-rata unified credit; marital relief
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Relief must be claimed correctly and on time
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Foreign tax credit
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Credits tax paid in one country against the other
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Limited to overlapping property/income
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US-UK income tax treaty
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Coordinates income and pension taxation
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Interacts with the “saving clause” for US citizens
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What about business structure, self-employment tax, and retirement savings?
The way a consultant trades shapes both their income tax and their eventual estate. Many operate through a personal company. A US LLC and a UK Ltd are taxed very differently across the border, and the “check-the-box” election, controlled foreign corporation rules, and GILTI can all bite where a US owner holds a UK company. Choosing the wrong wrapper can convert a clean succession into an annual compliance headache.
Self-employment tax and the totalization agreement
A US self-employed consultant faces a 15.3% US self-employment tax on top of income tax. The US-UK Totalization Agreement lets a consultant resident in the UK pay UK National Insurance instead, avoiding double social security charges — but only if they obtain a certificate of coverage from HMRC and attach it to the US return each year. It is not automatic; recent case law confirmed the exemption must be claimed with the certificate. Miss the annual filing, and the Internal Revenue Service can assess the full self-employment charge as though the agreement did not exist, which is an expensive and entirely avoidable mistake for a consultant billing at senior rates.
Retirement and equity planning
Retirement vehicles rarely translate cleanly. A SEP-IRA or solo 401(k) behaves differently from a UK pension under the treaty, and the interaction affects both lifetime tax and what passes on death. Consultants eyeing the Qualified Small Business Stock exclusion under §1202 should note that it requires a domestic US C-corporation — a structure that sits awkwardly with UK residence. Comprehensive planning, therefore, has to knit together the business wrapper, the pension, and the estate into one coherent design rather than three separate ones.
Which tools actually reduce a cross-border estate?
Lifetime gifting, trusts, and life insurance are the core levers, but each behaves differently in the two systems. UK gifts can fall out of the estate after seven years; the US annual gift exclusion is $19,000 per recipient for 2026. A grantor retained annuity trust (GRAT) or spousal lifetime access trust (SLAT) can work for US purposes yet be treated unfavorably for UK inheritance tax, so a US trust is never a UK trust by default.
Life insurance held in an irrevocable life insurance trust (ILIT) can provide liquidity to pay whichever death tax lands first, without swelling the taxable estate. Business succession — deciding who inherits or buys the consultancy, and on what terms — deserves the same attention as personal assets. The best estate-planning high-earning US consultants treat trusts as country-specific tools, tested against both regimes before anything is signed.
Anonymized case study
A US-citizen management consultant, “Daniel”, had lived in London for eleven years, trading through a UK Ltd and holding roughly £4.2m of assets: a London flat, US brokerage holdings, a solo 401(k), and retained company profits. Two problems surfaced. He had just crossed the 10-of-20-year line, so his worldwide estate now fell within the scope of UK inheritance tax, and he held US-situs shares subject to US estate tax. We mapped situs, claimed treaty relief to coordinate the two 40% charges, secured a certificate of coverage to stop the double social security tax on his consulting income, and layered an ILIT to fund the projected UK liability. His modeled combined death-tax exposure fell by a six-figure sum, with the business succession documented rather than left to chance.
Related reading from Jungle Tax
Speak to a US-UK estate planning specialist
Getting the sequence right — treaty claims, situs, trusts and business succession — is what protects a high earner’s estate on both sides of the Atlantic. Jungle Tax are Accountants for Creatives and cross-border professionals, and our dual-qualified team builds a single coordinated plan rather than two disconnected ones.
Email hello@jungletax.co.uk, call 0333 880 7974, or visit jungletax.co.uk to arrange a confidential review.
In practice, estate planning for high-earning US consultants is the exact scenario our cross-border specialists resolve every week.
Handling early estate planning for high-earning US consultants becomes a manageable, one-off exercise rather than a running risk.
