Gross mortgage lending by building societies and other mutuals reached £3.5 billion in June.
According to the latest figures from the Building Societies Association (BSA) lending over the first half of the year was up 28% from the same period in 2012 to £18million.
Mutuals now hold a 24% share of the gross lending market, up from 21% for the same time last year.
Building societies and other mutual lenders approved a total of 165,800 mortgages in the first half of the year, up 17% from 141,200 in the same period last year.
Brian Morris, Head of Savings Policy, BSA said: “Building societies and other mutual lenders have performed strongly in the mortgage market during the first half of the year, with net lending of £5.5 billion more than double the amount they lent in the same period last year.
“In contrast lending by other institutions, such as banks, was negative in the first half of 2013 at minus £3.0 billion as mortgage repayments outstripped new lending by those institutions.”
