Autumn Budget 2025: when it is and what will it contain?

Chancellor Rachel Reeves has confirmed that this year’s Autumn Budget will take place on Wednesday 26 November.

Reeves faces pressure to grow the economy and manage the UK’s finances as government borrowing costs hit a 27-year high.

Speculation over tax reform has been building throughout the summer, with potential changes to inheritance tax, capital gains tax, stamp duty and council tax.

Here, Which? rounds up the latest rumours — and what they could mean for your finances.

Inheritance tax on gifts

The Chancellor announced in last year’s Autumn Budget that private pensions would be included in the scope for inheritance tax (IHT) from April 2027. But rumours suggest she could be preparing to make further changes to the tax.

First reported by The Guardian, the Treasury is said to be considering a lifetime cap on the value of gifts that can be made before death, a tactic some people use to try to reduce their eventual IHT bill.

Under current rules, there’s no overall cap on how much you can gift tax-free during your lifetime, as long as you survive seven years after making the gift. A cap would place a limit on how much can be passed on during your lifetime.

It has also been reported that taper relief — which applies if you give away more than your nil-rate band of £325,000 before you die — could be adjusted or even removed.

Such a change would create a 'cliff edge' in the system, meaning beneficiaries could face a substantial tax bill if the person who made the gift died just one day short of seven years.

• Find out more: will inheritance tax rules on gifts be tightened? 

Council tax reform

According to a report in The Guardian, the Treasury is considering introducing a new annual local property tax with bills based on the current value of a home.

Details of how this would work have not been confirmed, although a shake-up to council tax has been discussed for years. 

The current system in England and Scotland is based on valuations from 1991. Wales uses 2003 property values, although the Welsh government has announced its own reforms to the system from 2028.

Council tax is currently divided into bands (A to H in England), with charges set by local authorities. In 2024–25, the average Band D council tax bill in England was £2,171. 

The outdated banding means some households in less valuable homes pay proportionally more than those in higher-value properties.

•  Find out more: council tax calculator 2025-26

Scrapping stamp duty 

In the same Guardian report, the Chancellor is said to be considering a new tax on home sales, which would replace stamp duty on owner-occupied homes.

Under the reported proposal, sellers – rather than buyers – would be responsible for paying the tax on properties sold for over £500,000.

Currently, first-time buyers pay stamp duty on any portion of a property's price above £300,000, as long as the home costs £500,000 or less. Previously, no stamp duty was due on the first £425,000 of a property costing up to £625,000.

Stamp duty is calculated in bands, with first-time buyers paying 5% on the portion between £300,001 and £500,000.

Existing buyers now pay 2% on the portion from £125,001 to £250,000, and 5% from £250,001 to £925,000. 

• Find out more: stamp duty calculator

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National Insurance on landlords 

The Times reports that the Chancellor is considering applying National Insurance to rental income for landlords – a move that could raise around £2.3bn a year.

At the moment, rent is largely exempt from National Insurance. But under the leaked proposals, landlords would pay the same 8% rate as the self-employed on their rental profits.

The estimate is based on Office for National Statistics figures, which show that 2.2 million landlords shared £27bn in rental income in the 2022-23 tax year. 

• Find out more: how rental income is taxed

New 'mansion tax'

A new ‘mansion tax’ is reportedly being considered by the Chancellor, according to The Times. The proposal would see capital gains tax (CGT) charged when someone sells their main home, based on the amount it has increased in value during ownership.

It’s expected the change would only apply to the most expensive properties. Reports suggest a threshold of £1.5m could affect around 120,000 homeowners, with higher-rate taxpayers facing CGT bills of almost £200,000.

CGT is already payable when you sell a property in certain circumstances – such as second homes, buy-to-let properties, or homes with substantial land or business use.

• Find out more: when do you pay capital gains tax?

Cuts to cash Isa allowances 

Earlier this year, the government was poised to announce a cut in the annual tax-free allowance for cash Isas. 

This move would have limited the cash portion of the current £20,000 yearly Isa allowance – which can be split between cash and stocks and shares Isas – to encourage investment instead of saving.

While these plans were temporarily set aside, they haven't been abandoned altogether. The government appears keen to get more people investing, and Reeves may revive the proposal in the Autumn Budget.

• Find out more: best cash Isa rates 2025