Autumn Budget 2025: What the Rental Income Tax Rise and Mansion Surcharge Mean for London Property Investors

The Autumn Budget 2025 was, on the surface, a quiet affair for property. Beneath the surface, it was anything but. Two announcements will materially alter the arithmetic of individual landlordship in England — particularly in London, where gross yields are already among the thinnest in the country. The first is a 2-percentage-point increase in income tax rates on rental profits, taking effect from 6 April 2027. The second is a brand-new annual surcharge on properties valued above £2 million, kicking in from April 2028. This article breaks down the mechanics of both, works through the numbers for a typical London scenario, and examines what the combined effect means for the ongoing debate between personal ownership and a limited company or SPV structure.

How Rental Income Tax Rates Are Changing from April 2027

From 6 April 2027, England will apply a separate, higher set of income tax rates specifically to property rental profits. The basic rate moves from 20% to 22%, the higher rate from 40% to 42%, and the additional rate from 45% to 47%.

The detail sits in HM Treasury's technical note published on GOV.UK on 26 November 2025, titled "Change to tax rates for property, savings and dividend income." The measure has since been enacted through Finance Act 2026, so this is no longer a proposal — it is law.

Scotland will set its own property income rates under its devolved tax powers. The new English rates apply to properties in England, Wales and Northern Ireland.

One partial offset is built in. The Section 24 mortgage interest tax credit — already a sore subject for higher-rate landlords — is set to increase in parallel, from the current 20% to 22%, matching the new basic rate. For basic-rate taxpayers, this means the credit and the rate rise cancel each other out, leaving no net additional cost. For higher- and additional-rate landlords, however, the credit rises only to 22% while the applicable tax rate jumps to 42% or 47%, meaning the gap between rate and credit widens rather than closes.

The Budget also confirmed that income tax thresholds will remain frozen until 2031. This so-called fiscal drag effect quietly pulls more landlords into higher bands each year as rental income and wages rise with inflation, even when headline rates appear static.

What the Numbers Actually Look Like for a London Landlord

The 2-percentage-point rise translates to an additional £20 of tax for every £1,000 of net rental profit, regardless of band. To make that concrete, consider the following illustrative scenario — simplified deliberately to show the mechanism; individual tax positions will always differ, and a qualified tax adviser should be consulted before drawing any conclusions about your own situation.

Hypothetical example: a £450,000 flat in an outer London borough (Zone 3–4), individual investor on the higher rate, no mortgage

This mortgage-free version understates the real-world impact for most investors. Where a mortgage is in place, Section 24 already restricts interest deductibility, and because the mortgage-interest tax credit also rises to 22%, the net effect for a mortgaged landlord is smaller than the headline rate rise suggests and varies from case to case, so a tax adviser should model it.

On a market-wide level, the National Residential Landlords Association (NRLA) has offered an industry projection that typical monthly rents in England could rise by £20–£25 as a result, and by more than £40 in London. The Office for Budget Responsibility's own view is that part of the cost will be passed through into rents and that, over the longer term, lower returns may reduce the supply of rental homes.

The High Value Council Tax Surcharge: What the "Mansion Tax" Actually Does

From April 2028, a new High Value Council Tax Surcharge (HVCTS) will add a fixed annual charge on top of existing council tax for properties valued at £2 million or more. For international investors holding prime London property, this is a new line item that goes straight into the net yield calculation.

The surcharge is banded as follows:

Critically, the HVCTS is paid by the property owner, not the tenant — so it sits directly against the investor's return, not the occupier's costs. Where a property is let, the landlord faces both the standard council tax (which a tenant may cover) and the HVCTS surcharge (which the landlord pays regardless).

Values will be reassessed every five years by the Valuation Office Agency, using 2026 prices as the baseline. From 2029/30 onwards, surcharge amounts are planned to rise annually in line with CPI.

The OBR modelled approximately 165,000 properties as falling within HVCTS scope in 2028/29 — less than 1% of England's total housing stock. That figure sounds small until you map it geographically: the overwhelming majority of affected properties are in London, concentrated in Prime Central London and the inner boroughs.

One important caveat: the detailed design of HVCTS remains under consultation. Exemptions and reliefs have not yet been finalised. Investors with properties approaching the £2 million threshold should track this process closely, as the final rules — expected to clarify in 2027 — may shift the scope materially.

Personal Ownership vs. SPV: How the Balance Has Shifted

The rental income tax rise does not touch corporate landlords. A limited company or SPV holding buy-to-let property continues to pay corporation tax on rental profits, and those rates were left unchanged in the Budget.

For context, corporation tax rates for 2025–26 and 2026–27 stand at:

Once the 2027 rates are in force, an individual higher-rate landlord faces 42% or 47% on rental profit while a company pays 19–25%. On headline rates alone, that gap is striking. But the headline is only part of the story.

The structural shift is already visible in the data. According to HMRC and Companies House figures, 66,587 new buy-to-let companies were incorporated in 2025 — a record level — demonstrating that tax pressure is accelerating the move to corporate structures across the market.

London Rental Market: The Yield Context That Makes This Matter

To understand why a 2-percentage-point tax rise carries more weight in London than anywhere else in the country, the yield numbers are instructive. According to Zoopla data, London's average gross rental yield sits at 5.1%, with an average monthly rent of £2,119 and an average sale price of £494,542. In inner boroughs, gross yields regularly fall below 5.2%. In outer areas — Newham, Barking and similar — yields can reach 6.8%, offering more margin to absorb additional costs. In Prime Central London, gross yields of 2.5–3.5% are common.

These figures reflect a market where the investment logic, particularly in prime and inner zones, has always rested more on capital appreciation than on income return. The tax changes do not alter that fundamental dynamic. What they do is squeeze already-thin income margins further, making the arithmetic less forgiving for investors whose return model depends on rental yield rather than long-term capital growth.

Optivest Note

In conversations with London-focused clients, two recurring mistakes stand out. The first is treating April 2027 as "far enough away" to defer any structural review. Setting up a corporate structure at the point of a new acquisition costs a fraction of what it costs to transfer an existing personally-held property later — because transfer triggers SDLT and CGT. If a portfolio expansion is on the horizon, the structure decision is worth making before the purchase, not after. The second mistake is modelling SPV tax savings without accounting for extraction costs. If the plan is to draw profits out as dividends rather than reinvest within the company, the combined corporate-plus-dividend tax burden can reduce the SPV advantage to something much smaller than the headline rate comparison suggests. The corporate wrapper works most powerfully when profits stay inside it.

Frequently Asked Questions

Are these tax changes confirmed law, or still subject to change?

The new rental profit tax rates — 22% basic, 42% higher, 47% additional — taking effect from 6 April 2027 have been enacted through Finance Act 2026 and are now statute. They are not a proposal; they are in force. The HVCTS, by contrast, has an April 2028 start date confirmed, but detailed design elements including exemptions and reliefs remain under consultation and have not yet been finalised.

Does the rental income tax rise affect properties held through a company or SPV?

No. The change applies to individual landlords paying income tax on rental profits. Limited companies and SPVs continue to pay corporation tax on rental income, at rates that were unchanged in the Budget. The indirect consideration is dividend taxation when profits are extracted: that combined burden should be modelled carefully before concluding a corporate structure is automatically more efficient.

Who pays the HVCTS — landlord or tenant?

The surcharge is payable by the property owner, not the occupant. Where a property is let, the tenant may be liable for standard council tax under the tenancy agreement, but the HVCTS is a separate owner liability that cannot be passed to the tenant in the same way. It reduces the landlord's net return directly.

Do these changes apply to Scottish properties?

The April 2027 rental income tax rate changes apply to properties in England, Wales and Northern Ireland. Scotland has devolved tax powers and will set its own property income rates separately. London and England-based investors are directly within scope.

A basic-rate taxpayer — is there actually a net cost?

Because the Section 24 mortgage interest credit is also set to rise from 20% to 22% in parallel, basic-rate landlords should see the rate rise and the credit increase cancel out, leaving no net additional tax burden. However, if total income — salary plus rental profit — pushes into the higher-rate band, the position changes. Individual modelling with a tax adviser is always necessary.

How will properties be valued for the HVCTS?

The Valuation Office Agency will conduct targeted valuations to identify properties within scope, using 2026 prices as the reference point. Revaluations will then take place every five years. The detail of appeal processes and any exemption criteria is still being worked through in the ongoing consultation, with final rules expected to be confirmed in 2027.

Disclaimer and Important Notes

This article is produced for general information purposes only and does not constitute investment, tax, or legal advice. Tax outcomes vary significantly based on individual circumstances, and nothing written here should be read as advice tailored to any reader's personal situation.

For questions about rental income taxation, Section 24 implications, and HVCTS liability, please consult an HMRC-recognised UK tax adviser or chartered accountant. For SPV structuring and property transfers, seek the guidance of an SRA-regulated solicitor. For mortgage-related decisions, obtain independent advice from an FCA-authorised mortgage broker.

Optivest is a property investment consultancy and FCA-authorised mortgage broker. We do not provide tax advice, legal advice, or immigration and visa consultancy. The numerical examples in this article are simplified and illustrative; they do not represent individual financial outcomes. The detailed design of the HVCTS remains subject to consultation, and specific provisions may change before April 2028.