The Bank of Gran and Grandad was open for business during the stamp duty holiday, gifting £437.3m towards buying homes for younger relatives over the last 15 months, according to Key.

The relief from the tax ends on Thursday, but during that time over-55s have given almost £1m a day to younger family members since Chancellor Rishi Sunak introduced the holiday last July.

The final phase of the stamp duty holiday – with the threshold having decreased from £500,000 to £250,000 on 30 June – is due to end on 30 September.

From 1 October, the threshold will return to £125,000 – or £300,000 for first-time buyers purchasing a property worth up to £500,000, concluding a tapered end to the current stamp duty holiday.

Prior to that, on 1 July, the stamp duty nil-rate threshold was reduced from £500,000 to £250,000 until the end of September.

The Treasury introduced the tax relief to revive the housing market, which had stalled following lockdown restrictions launched at the end of last March.

Gifting payouts hit their peak in June this year at £40.8m as the £500,000 nil rate ended, says equity release adviser Key.

The second biggest month was September last year when gifts hit £40.6m.

They hit a low of £13.2m in February in the run-up to the original deadline of 31 March for the stamp duty holiday, before it was extended in the 3 March Budget.

While to 21 September of this month, the Bank of Gran and Grandad have so far given £16.1m to younger relatives to get on the property ladder.

The average gifted for house deposits each month during the near 15 months of the stamp duty holiday is so far around £29m, or £56,000 per person.

Key chief executive Will Hay says: “While the stamp duty holiday helped to supercharge the older generations’ desire and ability to get children and grandchildren on the property ladder, the end of this incentive is unlikely to dim this appetite.

“Homeownership remains an ambition for many people – one that over-55s are eager to support – so all the signs suggest that many first time buyers will still benefit from older relatives’ generosity as well as no stamp duty on properties worth less than £300,000.”