For the half year to 30 September 2019, this represented a net market share of 12.3 per cent, according to the lender’s interim results.
The building society’s net mortgage lending also declined from £3.6bn to £3bn and the number of first-time buyers it helped fell from 40,500 to 33,500.
The society was the latest mainstream lender to be hit by payment protection insurance (PPI) charges as it said it received a “higher than anticipated” volume of PPI complaints and enquiries up to the 29 August deadline.
Its customer redress charge increased to £52m up from £15m the year before, primarily due to an additional £36m charge relating to PPI.
It October the society was ordered to refund 7,000 customers a total of £2m for failing to send or sending inaccurate PPI reminders.
Overall, Nationwide’s profit after tax came to £234m compared to last year’s H1 figure of £396m.
Joe Garner (pictured), chief executive, Nationwide Building Society, said: “Our trading performance was in line with our plans.
“We continued to grow our mortgages, deposits and current accounts, but at a more moderate pace, as we focus on broadening relationships with our members and helping to meet more of their financial needs.”