Nationwide, the UK's biggest customer-owned financial service, has posted a 56 per cent jump in annual underlying profit.
The company said its financial position remains robust and the leap in profits was a result of people demanding an alternative to the traditional banks.
According to Nationwide, it has seen a 58 per cent rise in customer numbers, as people switched over from another bank.
Nationwide's chief executive Graham Beale said: "Nationwide is uniquely well placed to meet the demands of the growing number of customers who are seeking a genuine and viable alternative to the established banks."
The bank also plans to issue a new form of so-called loss-absorbing debt in order to further improve its capital position.
Nationwide could potentially raise between £300 million ($454 million) and £500 million through the issue of so-called core capital deferred shares.
Loss-absorbing debt is used by financial businesses to protect themselves against any downturns in the market.
By Gary Cooper