HSBC was the cheapest mortgage lender in 2007, according to financial services research firm Defaqto.

An HSBC customer with a £50,000 mortgage on a standard variable rate would have repaid about £3,360 in interest last year.

This is nearly £75 less than Skipton Building Society, the second cheapest lender, and about £533 less than the most expensive.

Nationwide was the third cheapest lender, followed by Intelligent Finance in fourth and Direct Line in fifth.

Britannia, Standard Life Bank and Principality Building Society also made the top 10.

Halifax, the UK's biggest mortgage lender, came 17th and Northern Rock, the country's fifth largest, finished in 22nd spot.

David Black, Defaqto's principal consultant for banking, said: "While it is acknowledged that standard variable rate mortgages are only one type of mortgage, their importance may be increasing due to the knock-on effects of the credit crunch, making it more difficult to obtain attractive alternative deals."

Defaqto's research also shows that the average cost of a standard variable rate mortgage jumped 14 per cent in 2007 from a year earlier.

The Bank of England increased its key interest rate by half a percentage point during the year.

It currently stands at 5.5 per cent, but analysts expect that it could reach as low as 5 per cent before the end of 2008.