The rebranding began last May when the group's store in Heacham, Norfolk, was the first to receive the Heads makeover.
Nisa-Today's member Anglian Convenience Stores created the fascia as it was keen to retain its independent identity. It developed its own branding in partnership with the distributor, a practice that has since been adopted by other Nisa members.
Anglian Convenience Stores co-owner Peter Head said: "Nisa-Today's has given us the flexibility to make our individual mark on the Norfolk and Suffolk communities.
"Now on the completion of all 21 stores, we can concentrate on making the Heads brand work for us in communities throughout our region and plan for more stores further afield."