This compares to a rise of less than £5bn at all other lenders.
Mutuals approved 205,209 mortgages, which is a 32% market share of all mortgage approvals.
The trade body said that activity in the mortgage and housing markets has picked up over the past six months, ‘supported by strong wage growth, falling inflation and expectations that mortgage rates will continue to fall’.
Building societies’ mortgage balances accounted for 72% of the market’s growth in the last six months.
This follows 2023, when building societies were responsible for all the growth in the mortgage market, as overall mortgage balances at other lenders reduced over the year.
The BSA said that its members provided over 63,000 first-time buyer mortgages in the six months to September 2024, accounting for almost half (44%) of all their residential owner-occupier lending.
Service with a smile
Building societies performed better than banks on all measures of customer service.
For example, 93% of building society customers agreed their provider offered good customer service, compared to 87% of bank customers. And 86% of customers said their building society offered competitive rates, compared to 73% of bank customers.
Finally, 72% of building society customers said their provider is an important part of the community, compared to 54% of bank customers.
