HMRC Is Hiring Valuation Agents Ahead of New Mansion Tax Plans

The High Value Council Tax Surcharge, often referred to as a “mansion tax”, is a new annual charge on owners of residential properties in England valued at £2 million or more based on 2026 valuations. It was announced in the 2025 Budget and is expected to come into effect from April 2028. As part of the preparation for this policy, HMRC is hiring valuation agents to support the assessment of high-value properties and identify those that fall within scope. The charge will apply to property owners rather than occupiers and will be payable alongside standard Council Tax. Social housing will be excluded from the scope of this surcharge.

Key facts include:

• Threshold and Bands: Properties valued £2.0m–2.5m pay £2,500 per year; £2.5m–3.5m pay £3,500; £3.5m–5.0m pay £5,000; and homes over £5m pay £7,500 (based on 2026 valuations). These charges will rise each year with CPI inflation from 2029‑30 onwards.
• Scope: Fewer than 1% of homes in England will pay this surcharge. The Valuation Office Agency (VOA) will run a targeted valuation exercise during 2026 to identify all properties above £2m. Existing Council Tax will continue unchanged; the surcharge revenue goes to the Treasury (though collected by local councils).
• Frequency: Once identified, affected homes will be re-valued on a rolling basis every 5 years. A public consultation on details (reliefs, appeals, ownership rules etc.) was held early 2026. Further consultations will cover support for those who struggle to pay, reliefs/exemptions, and complex ownership arrangements.

Also Read: The Problems with the Mansion Tax: A Closer Look at Design Issues and Criticisms

Why Is HMRC Hiring Valuation Agents?

HMRC is recruiting up to 1,000 new valuation officers in anticipation of this surcharge. About a third of these roles will help implement the high-value surcharge, with the rest covering other priorities (such as customs checks on goods). The VOA (responsible for council tax banding) is being merged into HMRC in April 2026, and will use these extra staff to carry out property revaluations.

According to Treasury officials, these hires will peak in 2027–28 and 2028–29 to handle the extra workload. VOA Chief Executive Jonathan Russell told MPs that the agency plans to use “professional valuers” and additional support staff to assess homes potentially in scope. In fact, the VOA has said it will review not just homes over £2m, but also many houses from about £1.5m upwards, to make sure nothing is missed.

The Treasury’s own analysis suggests roughly 150,000–200,000 properties could be caught by the surcharge. For example, any house that might now be worth over £2m (and even up to £5m) is likely to be rechecked. These figures come from VOA estimates and parliamentary evidence; current Council Tax band data shows under 1% of homes are above £2m, but the broader review up to £5m (and including £1.5m+) expands the pool to about 0.5–0.7% of properties.

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What This Means for Homeowners

Who pays: 

Only owners of qualifying homes pay the surcharge – not tenants or lodgers. That means any mortgage or equity-share owner on the title at the valuation date (2026) would be liable.

Where it applies: 

Only homes in England are affected. Northern Ireland, Scotland and Wales use different systems. Social housing (council and housing association homes) is explicitly exempt.

How payments work: 

The new charges will be collected by local councils alongside normal Council Tax, but funds go to central government. Owners will get an annual bill. The surcharge is in addition to existing Council Tax, not a replacement.

Valuation and appeals: 

The VOA will use up-to-date market data (2026 values) and property attributes (size, location, features) to assess each home. In most cases the initial valuations will be done by officials (a “desk-based” valuation using sales data and maps). However, homeowners can challenge their surcharge valuation through a formal appeals process, details of which will be set out in new legislation. Affected owners should keep property records (purchases, improvements, planning info) handy.

Timeline: 

VOA valuations are expected to start in late 2026 or early 2027, so that bills can be ready for 2028. HMRC has not confirmed exactly when each house will be reviewed, but Jonathan Russell told MPs the review of high-value homes will begin this year (2026). Revaluations will then follow every five years for properties over the threshold.

Also Read: Mansion Tax in UK to Affect 200,000 Homes Starting in 2028

How We Help Deal With Mansion Tax

Apex Accountants can help high-value homeowners and professionals prepare for the new surcharge:

• Property Review: Analyse your property portfolio. If any home may be near £2m (or held by company/ trust), we check the likely 2026 value.
• Tax Planning: Advise on timing sales/purchases. Build the surcharge into financial planning. Model the annual cost and cash flow.
• Ownership Structuring: Guide on whether to own property in a company, trust, joint names or a partnership. We will stay up-to-date on the government’s consultation outcomes for complex ownership.
• Valuation Support: Help provide information to the VOA valuers. Ensure improvements and unique features of your property are documented to justify value.
• Appeals Assistance: If you believe an assessment is too high, we can work with you (and a surveyor if needed) to submit evidence and appeal the valuation.

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Call Anytime 0203 883 4777

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Conclusion

The new high-value Council Tax surcharge is now law, with detailed rules to follow a public consultation. From 2028 on, owners of homes worth £2m+ (and some up to £5m) will pay an extra annual tax. HMRC’s VOA is already preparing for this by recruiting specialist valuers and planning assessments for up to 200,000 homes. For those potentially affected, early preparation is key – understanding the bands and possible reliefs and keeping good records will make the transition smoother.