The government’s failure to extend the current stamp duty holiday could result in hundreds of thousands of property buyers missing out on the 31 March deadline.

Recent figures suggest some 325,000 buyers will not complete before the end of March deadline due to issues with conveyancing, surveying, mortgage and search services.

The chancellor’s decision to increase the threshold for paying stamp duty from £125,000 to £500,000 until the end of March next year is saving buyers an average of £4,400, with savings of up to £15,000 for properties worth £500,000 or more.

But with the property market struggling to cope with unprecedented demand from purchasers at the moment, it looks as though many people will not be able to take advantage of the tax holiday.

The backlog could see unexpecting homebuyers slapped with a total stamp duty bill of over £978m if the stamp duty holiday deadline is not extended, according to the latest research by GetAgent.co.uk.

The estate agent comparison site has been able to estimate the extent of the potential stamp duty bill for homebuyers caught in the current market logjam by analysing the latest transaction data to see how this will impact the markets in England and Northern Ireland.

The figures show that with England accounting for 97% of transactions, 315,534 sales could be impacted, while this drops to 9,466 in Northern Ireland.

With a current average house price of £261,795 across England, the 315,534 homebuyers who find themselves in property transaction limbo would pay no stamp duty as a result of the current holiday; if they were to complete before next year’s March deadline, that is.

The same applies for the 3,030 homebuyers waiting to complete in Northern Ireland with property prices currently averaging at £143,205.

But with these sales expected to fail to complete before the deadline, these homebuyers could be hit with a hefty stamp duty bill that they were not expecting.

With the average homebuyer in England usually paying £3,089 in stamp duty, this unexpected bill could come in at just under £975m. In Northern Ireland, this potential stamp duty bill is far lower but would still see homebuyers hit with an unexpected £3.446m.

In total, homebuyers could be hit with a stamp duty bill of £978,130,097 that they thought they had collectively saved.

Founder and CEO of GetAgent.co.uk, Colby Short, said: “Although the current stamp duty holiday has worked wonders in terms of reviving the property market, it has also presented its own problems for the industry.

“Such a heightened level of market activity has caused a huge backlog of sales waiting to complete and a large number of these transactions are predicted to miss next year’s stamp duty deadline altogether.

“As a result, many buyers could find themselves hit with an unexpected stamp duty bill having already stretched that little further during the offer process under the intention they would be saving this sum.

“It’s yet a further warning to those looking to buy to not overstretch themselves financially, whether it be with the expectation of paying no stamp duty, taking advantage of low-interest rates, or otherwise.”