Deposits for the best mortgage deals have soared by 43 per cent since the start of the credit crunch a year ago, figures show.

A typical homebuyer in England and Wales now needs to stump up £37,119 as a deposit to qualify for the most competitive mortgage deals, up 43 per cent over the past year from £20,980, research from mform.co.uk, the online mortgage company, shows.

Banks have tighten their lending criteria during the credit crunch, and borrowers who hold a large amount of equity in their home are being favoured at the expense of Britons with adverse credit histories.

Lenders are increasingly offering their best rates to borrowers with large deposits – typically 20 per cent or more of the property’s value – as property prices continue to tumble and fears over negative equity grow.

House prices are plummeting at their fastest rate since the housing market crash of the early 1990s, and the average home has lost £3,099 in value in the past month alone, tumbling to £169,316, according to the Halifax.

Best-buy mortgages now require an average deposit of 20.75 per cent, mform data shows, up from 11.75 per cent in August last year.

Popular two-year fixed rate deals have seen the biggest jump in the deposit required – from just 10 per cent 12 months ago to 23 per cent today.

London buyers need the largest deposit to buy the averaged-priced home of £345,000: they need £71,616, up 81 per cent from £39,580 a year ago, to snap up a best-buy mortgage deals.

Those in the north-east of England need the smallest deposit at £27,703. Nevertheless, that figure has increased by 84 per cent from £15,201 a year ago.

Francis Ghiloni, marketing and business development director at mform.co.uk, said: “There are still competitive deals and lenders willing to offer 95 per cent loans, but the most competitive offers are being restricted to people with big deposits or substantial equity.

“First-time buyers or those who have entered the property market recently will struggle to qualify for the most competitive rates.”

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