Pre-tax profits at lender OneSavings Bank increased fourfold in the first six months of the year in which it listed on the London Stock Exchange.

The Chatham-based firm – which includes Kent Reliance among its brands – saw profits before tax jump to £29.7m compared with £7.3m in the first half of last year.

Although the figure excludes £5.6m of expenses incurred during its launch on the stock market, the results have been described as a “strong start” to life as a listed company by chairman Mike Fairey.

The lender and retail savings company saw loans and advances grow by 13% in the first half of 2014 to £3.4bn, already surpassing the £3bn total figure for 2013.

Total new lending was up 78% to £649m while its returns on equity reached 30%, up from 20% on the same time a year earlier.

The company launched on the London Stock Exchange in June at 170p a share, raising £41.5m to reinvest in the business.

It became the first UK bank to list on the market in more than a decade, with the aim of challenging the big four of Lloyds, RBS, Barclays and HSBC, which have cut back on lending since 2008.

Chairman Mike Fairey said: “OneSavings Bank has made a strong start in its life as a listed company.

“The successful completion of the IPO [launching on the stock market] in June this year is a great tribute to the hard work of the executive management team and staff across the business over the last three and a half years in creating a unique retail-funded specialist lending business.”

OneSavings Bank chief executive Andy Golding said: “These results show the strength and opportunity in the business we have created.

“Our return on equity of 30% is a number of which we are particularly proud and this has been delivered at a time when we have also delivered a significant growth in lending.

“Underpinned by our strong retail funding base, the profitable lending growth, significantly improved efficiency and continued low level of impairments have all combined to drive a significant uplift in our earnings and returns.

“We have demonstrated our ability to deliver on the commitments we have made to our new shareholders and thank our staff for all their support during what has been a very busy period.”

OneSavings Bank was created in 2011 when struggling Kent Reliance Building Society was rescued with a £50m cash injection by US private equity group J.C. Flowers, which still holds a 65% stake in the company.

Its share price stood at 193p in early trading following the announcement.