Santander, which owns Abbey, said that it is responsible for one in seven new mortgage applications in the UK as it reported first-half year profit rises of 30 per cent in the UK to £790m.
Gross mortgage lending was £10.8bn in the first half, giving it an estimated market share of 16.3 per cent.
The Spanish bank, which bought Alliance & Leicester and part of Bradford & Bingley last year, lent 13 per cent more to small businesses and offered £2bn in net mortgage lending.
Abbey said it was well funded because its loan-to- deposit ratio was helped by the acquisition of B&B's savings book last year - meaning it was less reliant on wholesale funding so could continue to lend.
However, its figures at GBP 2bn are well down on the £22bn that the bank wrote in the first half of 2008, reflecting the market reduction.
Arrears in mortgages continue to rise, said the bank, although the number of properties in possession is down from March, while about nine per cent of Abbey's book is in negative equity.
The number of mortgages that are three months or more in arrears rose to 1.34 per cent in the second quarter, against 1.13 per cent in the first quarter, and properties in possession represented 0.06 per cent of the overall portfolio.
Antonio Horta-Osorio, chief executive of Abbey, said: "We have fewer repossessions on the book than in December. Low interest rates are helping consumers and we have taken a lot of actions to help customers in difficulty to avoid repossessions."
The bank said that it was on track to cut £180m of costs from its acquisition of A&L and said that it will reduce its combined workforce by 1,900 this year.
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