Older homeowners gifted an average of £42,500 to younger relatives to help them onto the property ladder, according to Key.
The average first-time buyer deposit is £57,278.
On a regional basis, older relatives gifted the largest amount to homebuyers in London at £102,826.
The South East at £61,500 and Wales at £44,200, were the next most generous.
In contrast, older relatives gifted £23,467 on average in the North West and £25,217 in Yorkshire.
Due to lower house prices, first-time buyers still benefitted from 76% of the average deposit needed in Yorkshire and 67% of the average deposit required in the North West.
In Wales, the East Midlands, Northern Ireland and the North East, the average gift from property wealth was higher than the average needed by a first-time buyer.
Of the £3.4bn released in property wealth in 2020, £755m was used to gift to younger family members.
Will Hale, chief executive at Key, said: “Finding almost £60,000 to use as a deposit for your first home is tough – especially in the current economic environment – and therefore it’s not surprising that many younger people have looked to take advantage of the stamp duty holiday.
“In 2020, older homeowners released almost £755m of equity in order to help younger members of their family meet a range of costs including supporting them with an average of £42,500 to use for a house deposit.
“For many people, these gifts will have been the enabler to them buying their first home and is a perfect example of how intergenerational wealth transfer can deliver positive societal benefits.
“The stamp duty holiday has certainly been a catalyst for more activity in this area but helping family is always a major motivation for older homeowners exploring their equity release options.
”That said, it is vitally important that homeowners get specialist advice if they do decide to use some of the value tied up in their home to help their families.
“Balancing generosity with their own financial security is vital and a good adviser will help them explore all their options.”