Autumn Budget 2026 UK Property Tax: CGT, Mansion Tax & What Homeowners Should Consider Now

Chancellor John Healey delivers the Autumn Budget 2026 on 28 October, and property taxation sits near the top of the agenda. The only fully confirmed measures so far are a new set of rental income tax rates (22%, 42%, 47%) from April 2027, and a mansion tax — officially the High Value Council Tax Surcharge — due to launch in April 2028 on homes worth £2 million or more. Capital Gains Tax changes, an ATED rise and an SDLT loophole closure on corporate-held commercial property are all being discussed in Westminster briefings, but none of it is locked in until Healey stands up at the despatch box.

Key takeaways

• Autumn Budget 2026 lands on 28 October 2026, with landlord and property taxation flagged as a central theme.
• From April 2027, rental income is set to be taxed at 22%, 42% and 47% — two points above standard income tax bands.
• The mansion tax (High Value Council Tax Surcharge) starts April 2028: £2,500–£7,500 a year on homes valued at £2 million or more, based on 2026 valuations.
• Roughly 145,000 UK homes — about 0.4% of the housing stock — are expected to fall inside the mansion tax net, concentrated in London.
• Current CGT rates on residential property (18% and 24%) remain law today, with no confirmed change announced for Budget day.
• Scrapping stamp duty or council tax in favour of a single annual property tax has been floated but is reportedly ruled out as a Budget-day measure.
• Homeowners near the £2 million mansion tax threshold cannot dodge the surcharge by selling later — eligibility is fixed by the 2026 valuation.

What is the Autumn Budget 2026 UK property tax package?

The Autumn Budget 2026 property tax package is less a single new policy and more a bundle of measures the Treasury has been building since late 2025, due to be confirmed or refined on 28 October 2026. It centres on three pillars: higher tax on rental income from April 2027, the mansion tax surcharge from April 2028, and speculation about further tweaks to Capital Gains Tax, the Annual Tax on Enveloped Dwellings (ATED) and Stamp Duty Land Tax (SDLT).

Pre-Budget previews published in August and September 2026 stress that Healey is expected to consolidate and confirm previously announced measures rather than unveil an entirely new property tax regime. Much of what will be "announced" on 28 October has already been trailed or legislated in earlier statements. The genuinely open questions concern CGT reliefs, ATED rates, and whether stamp duty reform gets a look-in.

Who does the Autumn Budget 2026 property tax affect most?

The changes are most likely to hit landlords with rental portfolios, owners of homes worth £2 million or more, and anyone holding UK property through a company or corporate wrapper. Owner-occupiers in ordinary homes below £2 million, without a second property, are the least affected group.

• Landlords and buy-to-let investors face higher tax on rental income from April 2027, cutting net yields immediately.
• Owners of £2 million-plus homes face the mansion tax surcharge from April 2028, even if they never planned to sell.
• Second-home owners are watching CGT closely, since any future rate rise would apply on sale of a property that isn't their main residence.
• Owners of enveloped dwellings (homes held via a company) could see ATED bills rise, and face closer scrutiny generally.
• Commercial property investors using corporate structures may lose an SDLT planning route if the Treasury closes the widely-reported loophole.
• Standard homeowners with one main residence under £2 million are largely untouched by the headline measures currently under discussion.

How will Capital Gains Tax change on property sales in 2026?

As things stand in September 2026, there is no confirmed change to CGT rates on residential property. Reports suggest officials are examining reliefs and allowances rather than the headline rates, but nothing has been announced.

Today's rules apply an 18% CGT rate within any unused basic-rate tax band and 24% above it on gains from residential property that isn't a main home. The annual exempt amount — the tax-free slice of gains everyone gets — sits at £3,000. These rates apply equally to second homes, holiday lets and buy-to-let properties.

Is there a Capital Gains Tax exemption for a primary residence in 2026?

Yes. Private Residence Relief continues to exempt gains on a main home from CGT under current rules, and nothing in Budget previews suggests this exemption is being removed. The relief only covers a property genuinely used as the owner's main residence, not a second home or investment property.

How likely is a Capital Gains Tax rise on second homes?

Plausible but not confirmed. Analysis of the Budget's overall direction notes a pattern of taxing unearned and property-related income more heavily than employment income, which keeps CGT reform on landlords' watch lists even without an official announcement. Owners planning a sale before 28 October should get valuation and gain calculations in order now, purely as a precaution.

What is the new mansion tax rate in Autumn Budget 2026?

The mansion tax — formally the High Value Council Tax Surcharge — is scheduled to start in April 2028, with bands published after a Treasury consultation that closed in July 2026. Autumn Budget 2026 is expected to confirm details rather than launch the policy from scratch.

The surcharge applies to English homes valued at £2 million or more using 2026 valuations, and charges a fixed annual amount rather than a percentage of value:

• £2,500 a year: £2m to £2.5m
• £3,500 a year: £2.5m to £3.5m
• £5,000 a year: £3.5m to £5m
• £7,500 a year: over £5m

What properties are exempt from the mansion tax?

Homes valued below £2 million fall outside the surcharge entirely. Guidance also confirms the charge applies to owners, not tenants — so a rented £2.5 million home still triggers the surcharge, payable by the landlord, not the occupier. No blanket exemption has been signalled for empty, inherited or business-use high-value homes at this stage.

Example: A London townhouse valued at £2.3 million in the 2026 valuation exercise would sit in the £2,500-a-year band from April 2028 — regardless of whether the owner sells or the market dips before then — because eligibility is locked to the 2026 valuation.

Is stamp duty being scrapped?

No — not for now. Reports from August and September 2026 indicate the Treasury has considered replacing stamp duty and council tax with a single annual property tax, but this has reportedly been ruled out as a Budget-day announcement, at least for the immediate term. A full property tax overhaul of that scale would likely require years of consultation, not a single Budget statement.

That does not mean stamp duty is untouched everywhere. The Treasury is reportedly modelling a closure of the SDLT loophole that lets buyers acquire commercial property through corporate structures at reduced tax rates. If closed, this would raise the effective cost of buying commercial property via a company wrapper — though residential stamp duty for ordinary home movers is not the target of this specific change.

Will ATED rise, and does the Budget affect property investors?

The Annual Tax on Enveloped Dwellings, charged on homes held inside companies, is one of the areas analysts flag as a plausible target for an increase, given the government's broader focus on taxing property held through corporate wrappers more heavily. Nothing is confirmed, but investors using company structures to hold residential property should assume scrutiny is increasing, not decreasing.

Property investors more broadly are affected mainly through the confirmed April 2027 rental income tax rise (22%/42%/47%), which analysts say could squeeze net yields enough to push some landlords toward incorporation, portfolio sales, or rent increases to offset costs. Combined with mansion tax exposure for higher-value portfolios, the direction of travel is clearly toward heavier taxation of property-related income and wealth relative to earned income.

Likely vs unlikely Autumn Budget 2026 measures

Practical steps before 28 October 2026

Homeowners, landlords and second-home owners can take sensible precautions now without overreacting to speculation.

• Get an up-to-date valuation if a property is anywhere near the £2 million mansion tax threshold — 2026 valuations determine future liability.
• Model rental yield under the 2027 rates (22%/42%/47%) to see whether incorporation or portfolio changes make sense.
• Review CGT exposure on any second home or buy-to-let property likely to be sold in the next 12 to 18 months.
• Check corporate holding structures for both residential (ATED) and commercial (SDLT) property, given reported scrutiny of enveloped ownership.
• Avoid panic-selling based on unconfirmed reports — nothing changes until Healey delivers the Budget on 28 October 2026.

Frequently asked questions

Is the mansion tax definitely happening in Autumn Budget 2026?

The mansion tax itself was already announced and is scheduled for April 2028. Autumn Budget 2026 is expected to confirm or refine details, not introduce the policy for the first time.

Will Capital Gains Tax rates definitely rise for landlords?

No rise is confirmed as of September 2026. Current rates of 18% and 24% remain in force, and any change would only take effect once announced on or after 28 October 2026.

Who has to pay the mansion tax?

Owners of English homes valued at £2 million or more as of the 2026 valuation, based on fixed annual bands of £2,500 to £7,500 starting April 2028. It applies to owners — including landlords of tenanted high-value homes — not tenants themselves.

Does the mansion tax replace council tax?

No. It is a separate surcharge collected alongside council tax, with revenue going to the Treasury rather than local councils.

Can I avoid the mansion tax by selling before 2028?

Selling before the surcharge starts avoids the charge for the new owner's future liability, but eligibility is fixed by the 2026 valuation for whoever owns the property at that point. You cannot retroactively avoid liability once the valuation exercise has captured a property above £2 million.

What happens to stamp duty in this Budget?

A full replacement of stamp duty with an annual property tax has reportedly been ruled out for now, though a narrower SDLT loophole closure on corporate-held commercial property is reportedly being modelled.

Book a RICS surveyor

Anyone with a home near the £2 million mansion tax threshold, or planning to sell a second home or buy-to-let property, should speak to a RICS-qualified surveyor now for an accurate, defensible valuation. A proper RICS survey supports both CGT planning around a future sale and clarity on mansion-tax exposure ahead of the 2026 valuation cut-off — decisions that are far easier to make with solid numbers than with headlines.

Survey Merchant provides vetted RICS surveyors across 100+ UK locations at fixed fees. Explore RICS Red Book property valuations, Level 3 Building Surveys, and Level 2 Home Surveys.