Coventry Building Society reported advances of £8.9bn in 2018, up slightly from £8.6bn in 2017, its annual results showed.
This helped increase mortgage assets by £3.4bn to £39.3bn, representing growth of 9%, three times faster than the market.
Mark Parsons, Coventry’s chief executive, said: “We’re doing what we’re here to do – providing access to competitive mortgages in a responsible and sustainable way.
“Our consistent outperformance of the market shows that we’re focusing on the right things – great value mortgages and fantastic service for borrowers and intermediaries alike.
“I want to thank our intermediary partners who’ve worked with us to deliver another year of robust growth.”