Gross mortgage lending from building societies reached £31.3 billion in the six months to March 2024, a market share of 30% of all loans.
The latest data, published by the Building Societies Association (BSA), shows that mortgage deposits with building societies rose by £8.6 billion in the six months to March 2024.
In the same period, mortgage deposits at other lenders fell by £10 billion.
The latest data on payment arrears shows that 0.25% of building society balances were in arrears at the end of the fourth quarter of 2023, compared to 0.69% in the overall market.
Between October last year and March this year, it recorded 191,241 mortgage approvals, giving it a 36% market share of all approvals.
Building societies helped 49,844 first-time buyers (FTBs) get onto the property ladder, accounting for 37% of all loans to housing associations.
Meanwhile, savings increased by £14.7 billion, a 35% share of total savings growth.
Earlier this week, a bill to allow building societies to boost lending became one of the last pieces of legislation to pass through Parliament ahead of the general election.
The amendment was introduced by Labor MP Julie Elliott in December as a private members’ bill to “level the playing field” between mutuals and banks.