Aldermore has established itself as a credible challenger to Britain's biggest banks by focusing on lending to small businesses and homeowners, and its initial pulbic offering (IPO) is likely to value the business at between 600 million pounds and 650 million pounds, a source familiar with the matter said.

Private equity firm Anacap and other investors will sell shares in the offer, which will result in about 40 percent of the bank being listed, Aldermore said on Tuesday.

At a valuation of 650 million pounds, that would see existing shareholders sell about 185 million pounds of shares alongside the new shares.

The bank had previously sought a valuation of about 800 million pounds when it considered listing last year, only to postpone the offering after a tumble in global stock markets and resistance from investors to its valuation.

Aldermore, founded in 2009 by former Barclays (>> Barclays PLC) executive Philip Monks and does not have a branch network, is still seeking a significant premium to its book value of about 450 million pounds.

It reported underlying pretax profit of 56.3 million pounds last year, more than double its 2013 profit, and said its return on equity was 15 percent, above the level of almost all European rivals.

Hedge fund investors Toscafund Asset Management LLP and Lansdowne Partners held a combined 8 percent of Aldermore and said when the bank previously intended to float that they planned to increase their shareholdings.

Aldermore did not mention the intentions of Lansdowne or Toscafund in its latest statement.

Credit Suisse (>> Credit Suisse Group AG) and Deutsche Bank (>> Deutsche Bank AG) are leading the listing and Lazard is advising.

($1 = 0.6471 pounds)

(Reporting by Steve Slater; Editing by David Goodman)

Stocks treated in this article : Deutsche Bank AG, Credit Suisse Group AG, Barclays PLC