Aldermore is in talks with South African group FirstRand over a possible takeover bid for the UK bank.
In a statement Aldermore confirmed the pair are in discussions over a “possible offer” of 313 pence per share, adding that the board is “likely to recommend a firm offer at this level”.
FirstRand, which owns FirstRand Bank, has until 5pm on 10 November to announce a firm intention of making an offer.
A FirstRand statement said: “The possible acquisition of Aldermore, with its unique operating model, market positioning and strength in deposit taking, would provide the ideal platform for FirstRand to fulfil this strategy on an accelerated basis.”
Aldermore stressed that there is no certainty of a firm offer being made.
The challenger bank saw new mortgage lending rise by 19% to £646m in the first half of 2017 from the corresponding period the year before.
Aldermore was founded by ex-Barclays director Phillip Monks in 2009.