The September figure was a 2% less than the £13.1bn lent in August.
Gross lending for the third quarter of 2011 is therefore an estimated £38.6bn, a 15% increase from the £33.5bn lent in the second quarter of this year and a 2% increase from the £37.9bn lent in the third quarter of 2010.
Bob Pannell, chief economist at the CML, said: "Both house purchase and remortgage lending appear to have fared well in September, but this is against the backdrop of subdued levels of activity.
"However, short-term economic prospects for the UK are not favourable. The housing market is very sensitive to wider household confidence, and this seems likely to weaken over the coming months in response to the latest spike in consumer prices and headline unemployment figures."
Duncan Kreeger, chairman of West One Loans, said: “High street lenders are retreating from the market or only targeting very wealthier borrowers. That’s created a lending void, particularly for people who want to invest in buy-to-let property.
“They are turning to bridging lenders to fill that void. While gross mortgage lending is effectively stagnant, gross bridging lending has risen 46% in the last year and, according to our forecasts, will hit £800m by the end of 2011.
“With mortgage lending so painfully subdued, bridging finance is providing the lifeline that private investors and buy-to-let landlords need.”
Richard Sexton, director at e.surv chartered surveyors, said: “With inflation so high, the year-on-year rise is actually little to celebrate. The reality is mortgage lenders are actually retreating from high loan to value lending.
“Their confidence has been further dented by the economic crises that is running amok in the eurozone, and by the cracks beginning to appear in the government’s growth strategy. With the supply of credit so restricted, there is almost no scope for them to grow their loan books, so they are understandably playing it safe and focusing on targeting borrowers with big deposits.
“Purchase approvals with a deposit of 25% fell to their lowest level in six months in September because lending criteria on high LTV products is so tight. First-time buyer numbers have fallen to their lowest since November last year, which is a sure sign the mortgage market is struggling.”