Yorkshire Building Society advanced £4.1bn in new mortgage lending in 2011, an increase of 46 per cent on the £2.8bn it lent in 2010.
YBS says customer deposits funded 97 per cent of loans advanced, up from 94 per cent in 2010.
The group average loan-to-value for the year was 54 per cent, down from 56 per cent in 2010.
Member savings balances increased by 21.4 per cent, up from £21.4bn in 2010 to £26bn in 2011.
Pre-tax profit increased 12 per cent, from £115.4m in 2010 to £129.7m in 2011.
YBS has a core tier 1 capital ratio of 12.6 per cent, up slightly from 12.4 per cent in 2010.
YBS chief executive Chris Pilling says: “I am extremely pleased to report very strong financial results for the Yorkshire in 2011. This performance shows significant growth in mortgage and savings balances, increased level of operating profit, stable net interest margin and robust capital and liquidity positions despite the continuing challenges presented by the economic and market conditions.”