Mansion Tax Drives UK Home Sales to Bunch Just Below £2m Threshold

House sale prices in the UK have shifted sharply just below the £2m mansion tax threshold. This bunching effect provides the first hard evidence that the new levy is already distorting market behavior.

The share of sales priced in the £10,000 band immediately below £2m increased from 0.44% to 2.27%. Conversely, the proportion of transactions at exactly £2m fell from 5.69% to 2.70%.

Statistical evidence confirms pricing distortion

Tax Policy Associates compared completed sales from December 2025 to July 2026 against the prior year. The analysis reveals a significant deviation from natural price clustering patterns.

Confidence interval tests show the shift at £2m exceeds expected random variation. A similar, though smaller, effect appears at the £3.5m threshold, confirming targeted seller behavior.

Broader market impact remains unproven

Researchers found no clear evidence that the tax has reduced property values more widely. Current data limitations prevent detection of the broader effects anticipated by the Office for Budget Responsibility.

The study primarily presents a negative result regarding general price suppression. Publishing these findings ensures transparency about the tax's current limited scope.

Valuation rules prevent total tax avoidance

Selling a property for £1,999,999 does not guarantee escape from the annual charge. The Valuation Office assesses homes using comparable sales and characteristics rather than transaction prices.

The tax applies to valuations as of April 2026, starting in April 2028. Sellers may continue to adjust pricing strategies as the implementation date approaches.