The mutual also said it had helped 24,000 buyers buy their first home, an increase of 9% on the year before.
Profits at the building society fell from £317m to £203m after a number of one-off costs which included £75m for the Financial Services Compensation Scheme and the bank levy, higher than last year’s £50m.
Other exceptional costs included £61m to cover restructuring measures.
The mutual said its underlying profit for the year was £304m, up 10% from £276m last year.
Nationwide also said it had set aside a £103m provision against potential claims for mis-sold Payment Protection Insurance compared with £16m a year ago.
Graham Beale, chief executive at Nationwide, said: “The key strategic delivery in the past year has focused on growth across all of our principal product lines. We have bucked market trends by increasing our gross lending by 44% to £18.4bn demonstrating our commitment to supporting growth in the economy as well as meeting the needs of borrowers, especially first-time buyers.
“Our plan for the forthcoming year is to do more of the same, to focus on the needs of our members and customers, to play our role in supporting the UK economy and to continue to invest to deliver improved levels of service, efficiency and product choice.”
