The average price of a home coming up for sale in Britain's richest borough has fallen by nearly £100,000 in a month as sellers compete for buyers. 

The current average new asking price of a home in the Royal Borough of Kensington and Chelsea was £1,552,970 in August, says Rightmove.

A month ago, the figure was £1,648,148, a difference of just over £95,000. 

A buyer spending £1,648,148 on their next home would need to pay £111,528 in stamp duty.  

Sellers in some London boroughs are resorting to drastic action to try to tempt affordability-stretched buyers and secure a sale, Rightmove claims.

The online property portal said the number of available homes for sale in London had reached its highest level for 16 years. 

The glut of homes for sale in London was 'leading to fierce competition among sellers to tempt buyers in the costliest part of Britain'. 

Across London, average newly listed asking prices fell 4.4 per cent month-on-month in August, equating to about £30,000 lopped off a new asking price.

This month, four councils in London complained to the Government that plans for additional council tax on homes worth more than £2million would hit their residents hardest.

The leaders of Kensington and Chelsea, Richmond, Wandsworth and Westminster councils told Chancellor John Healey that 55 per cent of the projected amount raised will be from their boroughs.

The high value council tax surcharge, dubbed the mansion tax, is an annual levy of between £2,500 and £7,500 scheduled to take effect in April 2028.

A Treasury spokesman said it will address 'a long-standing unfairness in our country' where a Band D home in some parts of England is liable for more council tax 'than a £10million mansion in Mayfair'.  

It's not just London affected by price drops

August saw the largest average asking price drop for house prices in this summer month since 2018, Rightmove said. 

The average price of a newly listed home in Britain fell by 2 per cent this month, to £364,999, representing a drop of £7,360, much larger than in a typical August.

The decline means average asking prices are now 1 per cent lower than a year ago, as mortgage rate rises in recent months have cooled the market.

Rightmove said the volume of available homes for sale across Britain hit a 12-year high in August for this time of year. 

Combined with the usual summer holiday slowdown, sellers have had to reduce their pricing expectations. 

In the North West, the average asking price rose by 1.9 per cent annually but in London it fell by 3.1 per cent. 

Colleen Babcock, a property expert at Rightmove, said: 'This month's larger-than-usual August price drop is a sign that many sellers are recognising the reality of the market and pricing much more competitively from day one.'

She added: 'Buyers have the widest choice of homes for sale at this time of year in more than a decade, so standing out on price for the right reasons is hugely important.

'One tactic some sellers are using when considering lower offers on their home is to also make a lower offer themselves on their onwards purchase, to see if they can make up the difference.'

Rightmove revised down its house price forecast for 2026 from a 2 per cent increase to between flat growth and a 2 per cent drop in average seller asking prices over the full year. 

Separate data from Hamptons said landlord buyers were capitalising on the sluggish housing market to 'drive a hard bargain' and push for steep price reductions. 

Hamptons said sellers were increasingly willing to accept these lower offers. 

Many leasehold flats, particularly ones with no outdoor space and only one bedroom, are proving particularly hard to sell. 

A previous analysis by property website Zoopla found that across most of England, the majority of leasehold flats listed for sale in 2025 had not sold within six months.  

Rightmove said it had seen a 'mini bounce' in buyer demand since Andy Burnham became prime minister.

But it said the changing picture for mortgage rates, alongside geopolitical uncertainty and the Budget in October were creating housing market uncertainty.

Babcock said: 'The mini Burnham bounce and some renewed general optimism have brought a degree of improvement to the market as a whole in recent weeks.

'Whether that develops into a more sustained recovery will likely depend on confidence, mortgage rates and the new Chancellor's first Budget this autumn.'