Treasury inspectors tasked with assessing a new punitive housing levy will reportedly use a checklist of features to determine property values, including scenic views, conservatories, and large garages. This approach, outlined in an HMRC tax manual obtained by the Conservative Party under freedom of information laws, suggests a detailed evaluation beyond obvious signs of opulence.
Sources indicate that inspectors may also consider the number of bedrooms and bathrooms, the presence of balconies, roof terraces, annexes, outbuildings, and whether a property is located within a gated community. For rural properties, the inclusion of farmland and stabling for horses will also be a factor. Ministers have previously confirmed that valuation agents can conduct internal inspections to verify if homes exceed the £2 million threshold.
Refusal to allow an inspection by HMRC officials could result in a criminal offense, carrying a fine of up to £200. Tory chairman Kevin Hollinrake criticized the policy, calling it a "sinister reality of Labour's secret council tax snooping plot" and expressing concerns about privacy invasion.
The high-value council tax surcharge, commonly referred to as a mansion tax, is scheduled to take effect in 2028. It was announced in the previous year's budget by then-Chancellor Rachel Reeves. HMRC agents are expected to utilize third-party data and publicly available information, supplemented by internal inspections, to value properties.
The government's budget watchdog estimates that approximately 165,000 properties will be subject to the surcharge in its first year, increasing to 167,000 by 2030. The levy will be implemented in four price bands, with annual charges ranging from £2,500 for properties valued over £2 million to £7,500 for those exceeding £5 million. This re-evaluation is anticipated to impact homes across council tax bands F, G, and H. A government spokesperson stated that the surcharge will affect less than 1% of properties in England.