United Co-operative bosses have set the society a target of 50 new stores for 2007.
It revealed its aim after a merger with Leeds and Sheffield Co-ops, which will mean it will operate more than 600 stores and employ about 11,000 staff by February.
The society is also in merger talks with the Co-operative Group, which could create the largest consumer-owned co-operative group in the world.
In an attempt to boost its store portfolio, United Co-op has set up a website - www.unitedacquisitions.co.uk - which will provide information and a contact process for users who have potentially suitable sites for sale.
United Co-op property group general manager Derek Fogg said: "This website is a valuable tool that will allow us to build relationships with potential vendors."