Nationwide Building Society will pay its customers £340m through payments to their current accounts after reporting a 40% leap in annual profit driven by the succession of interest rate hikes.

It said it would make a £100 payment to eligible customers next month, adding that this will be its first such distribution and that the society aims to repeat this in future years.

Nationwide reported pretax profit of £2.2 billion for the year to 4 April, up from £1.6bn in the previous year. However, net lending fell from £7.1bn to £3.3bn in a tighter mortgage market.

CEO Debbie Crosbie said the unusual payout to customers was possible because the lender was a building society that they owned.

The lender nonetheless said that Britain’s tough economic outlook could lead to more customers falling behind on loan repayments and it set aside £126m to cover possible soured loans, compared with the release of £27m of reserves the previous year.