Q&A: Your quickfire questions about ‘Mansion Tax’ answered

Mansion tax is due to hit owners of high-value properties in some eighteen months’ time. The charge won’t affect most UK homeowners. But if your property falls into the £2M+ bracket (or sits just outside), you may have questions. Here’s what we know so far:

What is the mansion tax?

“Mansion tax” is the informal name for a new charge called the High Value Council Tax Surcharge, or HVCTS. Then-Chancellor Rachel Reeves announced it in the November 2025 Budget.

The HVCTS charge should make the council tax system fairer. As it stands, owners of lower-value properties can pay more council tax in relation to their property’s value than owners of very high-value homes. It’s hoped that the surcharge will address this imbalance.

The charge comes into effect in April 2028.

Who will pay it?

The surcharge applies to homeowners whose property is valued at £2 million or more. It doesn’t apply to tenants of similar properties. The valuation is based on what the Valuation Office judges the property to be worth in 2026.

The annual charge is structured in bands:

From the 2029–30 tax year onwards, the charge will increase each year in line with the Consumer Prices Index (CPI), the standard measure of inflation.

Around 183,000 homes in England are estimated to be worth £2 million or more. A further 75,000 properties sit just below that threshold.

Will HMRC visit your home to value it?

This has been one of the most talked-about aspects of the new charge. Early reports suggested that HMRC inspectors could be sent to properties to carry out valuations in person.

HMRC foresees making most banding decisions using existing information. As such, it will forgo the need to visit properties in person. Its valuers will consult multiple publicly available sources to ensure assessments reflect properties’ current market values.

However, home visits have not been ruled out entirely. Where an inspection is warranted, valuers will look at details such as the number of rooms, storeys, bedrooms, and bathrooms. Homeowners who refuse to allow an inspection could be committing a criminal offence, incurring potential fines of up to £200.

How will properties be valued?

Valuations will be based on a property’s market value in 2026. HMRC proposes revaluations every five years. The Valuation Office, which is currently undertaking this exercise, will carry out these valuations.

If you think your property’s been banded incorrectly, you’ll have the opportunity to challenge the decision. This is expected to be particularly relevant for properties whose value sits close to a band threshold.

Are there any exemptions?

Yes. Several exemptions apply, including:

• Purpose-built student halls of residence,
• Properties owned by a sovereign nation,
• Properties owned by a registered social housing provider, and
• Care homes.

Newly built properties owned by developers will also receive an exemption or discount until the earlier of the first sale or twelve months after practical completion.

Could the threshold change?

Mansion tax thresholds could change. Reports suggest the lower qualifying rate could be reduced from £2 million to £1.5 million in the future.

The Government has not yet confirmed this, though. Analysis by Tax Policy Associates estimates that around 150,000 additional homes could be affected if the threshold were reduced.

Until any formal announcement, the confirmed threshold remains £2 million.

What does this mean for buyers and owners?

For most homeowners and buyers, the mansion tax will not apply directly. Most properties in the UK fall well below the £2 million threshold.

That said, there are a few things worth bearing in mind:

If you own or are buying a high-value property

It’s sensible to get an independent view of your property’s likely valuation now, before the Valuation Office completes its assessments. If your property sits close to a band boundary, it may be worth taking professional advice on whether a challenge would be appropriate.

If you’re buying in an area where property values are high

Pertinent to parts of London and the South East in particular, it’s worth factoring the surcharge into your long-term affordability calculations, not just your mortgage costs.

If you’re a landlord with high-value properties

The mansion tax charge falls on the owner, not the tenant. That’s an additional running cost for landlords to factor into their financial planning.

Where mansion tax sits in the bigger housing market picture

The mansion tax is one of several property tax changes either confirmed or currently under discussion. The Government has already confirmed that property income tax rates will rise from April 2027. The future may bring higher costs for many landlords.

Wider reforms—such as replacing stamp duty or council tax with a single annual property tax—haven’t gone ahead. Still, experts warn that thresholds and charges introduced under new property taxes may be reviewed or extended over time.

The property tax landscape is shifting. Whether you are a buyer, a homeowner, or a landlord, staying informed about what is changing and when puts you in a much stronger position to plan ahead.

If you have questions about how any of the above could affect your mortgage plans, our advisers are happy to help. Get in touch to discuss your situation.