Wealth taxes: high risk, unworkable and anti-growth

Dan Neidle sends me Tax Policy Associates thinking on tax

A UK wealth tax is often promoted as an easy revenue-raiser that would only affect the very rich. Our analysis finds the opposite: the revenue is highly uncertain, and would arrive only after years of complex implementation. Most importantly, the tax would lower long‑run growth and employment, thanks to a decline in foreign and domestic investment. It would make UK businesses more fragile and less competitive, and create strong incentives for capital reallocation and migration. There are better solutions to the many problems with our tax system.

This report summarises the UK wealth tax proposals, analyses the claimed revenue yield, and looks at the potential downsides and risks, and the policy alternatives. We compare the new proposed wealth tax with the older wealth taxes that have largely failed and been repealed. Finally, we suggest better and less risky ways to tax wealth in the UK.

Executive summary

This very brief summary links at each point to the detailed analysis below. You can also navigate with these buttons:

1. Economic impact: growth, investment, startups

Wealth taxes are anti-growth. Penalise saving & capital formation. Effective tax rates can exceed 60%+ for modest‑return assets. High effective rates. Growth impact. Employment impact.
Evidence. International modelling of comparable proposals shows ~2% (US) to ~5% (Germany) long‑run GDP hits, plus large impact on employment; UK exposure may be greater. US studies · German study.
Startups & capital‑intensive firms face liquidity squeezes. Owners may be forced to sell or pull cash from the business. Valuation difficulties. Liquidity problem · Capital‑intensive impact.
Higher dividend payouts to fund tax mean lower reinvestment. Evidence from Norway & other studies. Dividend response.
Foreign direct investment would fall. Tax must catch foreign owners or is easily avoided. That deters future FDI and prompts withdrawal of current FDI. FDI analysis.
Makes UK business uncompetitive. Because a UK Ltd’s foreign subsidiaries are subject to the UK wealth tax; its foreign competitors are not. Competitiveness.
Worsening recessions. In a downturn, capital and the taxes on it usually fall automatically – “automatic stabilisers” for the economy. Wealth tax bills barely change. Wealth taxes provide a shock during periods of financial stress.
These factors are both more consequential and more complex than the “will they leave?” debate that’s currently playing out in the media.

2. Revenue risk: headline sums are fragile

Claims of £10bn to £25bn a year revenue rest on optimistic behaviour assumptions. Using higher (still plausible) avoidance/migration elasticities cuts receipts sharply. Revenue analysis. The numbers.
80% of projected yield comes from ~5,000 people; ~15% from ten people. A handful changing residence or valuations could remove billions. Migration risk. Worse than non-dom response.
Even proponents’ “low response” scenario implies £200bn of lost capital; “high” ~£500bn. That erodes other tax bases. Capital at risk.
Historic data are misapplied. Past wealth taxes had low rates, wide exemptions and applied broadly; new UK proposals are the opposite. Compare designs.
The UK would be an outlier. No developed country in the world has both a significant wealth tax and a significant inheritance tax. Nobody has implemented a wealth tax of the type proposed. International comparisons.
Requires an unprecedented wealth exit tax to stop large-scale capital flight. But fear of an incoming wealth exit tax would trigger a wave of exits, and the tax would deter entrepreneurs and others from coming to the UK. Undermines the Government’s new FIG regime. Wealth exit tax.

3. Implementation & better options

Complex to legislate & administer. Realistically multi‑year build; no cash until January 2029. Implementation timeline.
Existing wealth taxes abroad work only with big carve‑outs. Spain exempts business assets and collects very little – a deliberate decision of a socialist government to minimise economic damage. Norway/Switzerland heavily discount or cap. International evidence.
Valuation creates an administrative burden far beyond that seen in income or consumption taxes. Valuation difficulties.
Fix current UK wealth taxes instead. Reform land tax, capital gains tax, and inheritance tax. All could raise revenue more fairly, more efficiently and faster, with fewer risks. The UK needs tax reform across a swathe of existing taxes. Policy alternatives.
The apparent polling support for wealth taxes is fragile, based upon questions that provide no context and reveal no trade-offs. The mansion tax was popular – until it wasn’t. Polling.

Bottom line: An annual UK wealth tax is a high‑risk, low‑certainty revenue bet that could harm growth. Better‑targeted reforms can tax wealth more effectively with far less collateral damage. See our recommended reforms.