HMRC is set to deploy valuation agents to homes across the UK to determine whether properties fall under the new High Value Council Tax Surcharge, often referred to as the mansion tax. These agents will be able to demand entry to properties to assess if they are worth over £2m.
The mansion tax levy, first introduced by former chancellor Rachel Reeves in last year’s autumn budget, is scheduled to take effect in April 2028. The charge will apply to properties valued over £2m, with an additional annual levy ranging from £2,500 to £7,500, depending on the property's worth.
Property owners who refuse entry to inspectors may face fines of up to £200 and could be committing a criminal offence. The Valuation Office, part of HMRC, states that inspections will be required where "attributes can only be confirmed internally or a re-measurement is required." Inspectors will assess property interiors, including size, architectural style, and the number of bedrooms, bathrooms, and storeys.
The mansion tax charge is now expected to affect 165,000 homeowners in its first year, an increase from the originally forecast 120,000. This means an additional 45,000 homes will be subject to the levy, although thousands are expected to successfully appeal the tax.