A 2028 UK mansion tax would tax homes over £2M, but flawed valuations may unfairly increase burdens.

Chancellor Rachel Reeves' proposed mansion tax, set for 2028, will impose annual council tax surcharges on homes valued over £2 million, with rates from £2,500 to £7,500 based on value. The plan relies on revaluing properties, but experts warn computer-generated assessments may overestimate values by up to £30,000, risking unfair tax burdens. While social housing above £2 million is exempt, critics argue the policy unfairly targets private homeowners, especially in London, and raises concerns about accuracy and equity in valuation methods.