What Britain can learn from international wealth taxes

The Autumn Budget 2026 did not introduce a comprehensive annual wealth tax. Instead, the Government has pursued more targeted measures. Fiscal drag is widening the effective IHT base: the £325,000 nil-rate band remains frozen through 2030–31, so nominal growth in asset values can increase the proportion of an estate exposed to IHT even though the headline rate remains unchanged. The Government has also pursued the High Value Council Tax Surcharge, intended from April 2028 for owners of higher-value English residential property.

HVCTS is not a net wealth tax: it is a property-based charge rather than a tax on an individual's overall assets less liabilities. But it illustrates how governments can increase taxation of accumulated wealth without introducing a formal net wealth tax.

International experience is more nuanced than the headlines

A recurrent wealth tax generally charges an individual's net assets whether or not they produce enough income to fund the liability. This can matter particularly for founders with wealth concentrated in private companies and families holding property or other hard-to-value assets.

The OECD recorded a marked decline in recurrent net wealth taxes: 12 OECD countries operated them in 1990, compared with four in 2017. Limited revenues, administrative complexity and economic-efficiency concerns have featured in debates around repeal.

Countries retaining or modifying these taxes show why the picture is more complex.

Switzerland continues to levy wealth taxes at cantonal and municipal level. Research suggests taxable wealth responds to different rates, but migration is only part of that response.

Norway also taxes net wealth. Recent research has identified migration among some very wealthy taxpayers without finding a significant reduction in investment by businesses owned by those who moved. An owner's departure should not automatically mean the departure of the underlying business.

France replaced its former general wealth tax with the Impôt sur la Fortune Immobilière, focused principally on real estate. In 2024, approximately 186,000 households were assessed, generating around €2.2 billion from €467 billion of declared net taxable real-estate assets.

The UK surcharge is structurally different, but both approaches show how governments can target particular forms of wealth without taxing an individual's entire net asset base.

The UK tax base affecting private wealth is broadening

From 6 April 2025, inheritance tax moved from domicile to long-term UK residence as the principal domestic connecting factor for overseas assets. Broadly, someone UK resident for at least 10 of the previous 20 tax years may become subject to UK IHT on overseas as well as UK assets. Depending on residence history, exposure can continue for between three and ten tax years after departure.

A previously announced change will also apply to deaths from 6 April 2027, when most unused pension funds and pension death benefits will be brought within estates for IHT purposes.

None of these measures is a recurrent net wealth tax. Together with frozen thresholds, however, they explain why internationally connected families increasingly consider the cumulative taxation of wealth during life and on death.

International estates require a treaty analysis

UK domestic rules are not always the end of the analysis. The UK has a limited network of estate-tax treaties, and domicile can remain relevant under some older conventions.

The UK–Italy Estate Duty Convention is one example: within its scope, it can affect taxing rights and double-tax relief on death notwithstanding the UK's domestic move to long-term residence.

Treaty protection cannot be assumed. Residence history, domicile, asset location and the relevant convention may all matter.

Mobility is about more than tax

Tax can influence where internationally mobile families live and hold wealth, but relocation is rarely determined by one measure.

Moving an individual does not necessarily move a company, alter an asset's location for tax purposes or change the treatment of an existing trust. It can also affect business management, succession, immigration and reporting.

For internationally mobile families, founders and family offices, the question is broader than whether Britain has a formal wealth tax. It is which countries can tax accumulated wealth, which connecting factors they use, which assets are within scope and whether treaty protection changes the result.

International experience does not tell us simply that wealth taxes work or fail. It tells us that design matters, mobility matters and the family's wider circumstances matter too.