Pepper Money will apply for a banking licence, with several senior hires confirmed to support the move.
The lender announced it would seeking authorisation for a banking licence from the Bank of England, having already begun discussions with the Prudential Regulation Authority and the Financial Conduct Authority.
Pepper Money entered the mortgage market in 2015 and only operates through intermediaries - targeting those borrowers experiencing difficulty getting a loan with high street banks and building societies.
Laurence Morey, chief executive of Pepper Money, said the move was designed to strengthen the lender’s ability to support those customers who are underserved by high street lenders.
He said: "It will enable Pepper to expand the range of solutions we provide to our core customers – including people with complex incomes, the self-employed, those who fall outside high street credit scoring, first- time buyers and buy-to-let landlords – as well as securing more diverse funding sources for the business in the form of retail deposit funding."
Mr Morey said Pepper would also consider targeted acquisitions to increase the range of solutions provided to customers.
To support the application, Pepper has made three appointments to its leadership team - subject to regulatory approval.
John Maltby will join as non-executive chairman, having previously worked as group commercial director at Lloyds Banking Group and chief executive at Williams and Glyn.
David Bowles will join as chief risk officer, having worked with challenger banks Shawbrook Bank and Monzo, and Bob Golden has been appointed as chief commercial officer, moving from his current positions at Close Brothers.
Mr Morey said: "It is a tribute to the strength of Pepper’s achievements that we have been able to attract such high calibre individuals and I look forward to working with them all."