The price tag for TM Retail - which operates the Martin’s, McColl’s and Forbuoys fascias - is expected to be £200m to £250m.
Private equity firms Montagu and Electra control TM Retail and called in banking group Goldman Sachs to find a buyer for the business more than 12 months ago.
TM Retail has 314 convenience stores and 118 variety stores, as well as 759 confectionery, tobacco and news stores.
Last February, supermarket group Somerfield and TM Retail, joined together to test a Somerfield Martin’s convenience store format.
Somerfield supplies fresh and chilled food on a six-day-a week delivery cycle while TM Retail provides the premises, the staff, and 1,500 news and confectionery lines. The venture consists of six stores so far.