Developers want to move existing entrances at the Harry Tuffins Supermarket in Craven Arms and replace them with a single entrance.
Plans submitted to Shropshire Council also include a possible expansion of the car park, developing a new garden centre and creating staff accommodation.
The supermarket is part of the Craven Centre just off the A49 which would also be given a facelift as part of the development, which could also create a number of local jobs.
The Midcounties Co-operative took over Harry Tuffins in a shock multi-million pound deal earlier this year.
And it pledged to secure jobs and 'significantly invest in the estate'.
Stephen Cox, senior partner at Gould Singleton Architects who are managing the application for Midcounties, said there was no fixed date for the expansion plans.
He said: "This is a renewal of a former plan from two years ago and the time of when this redevelopment may go ahead in Craven Arms is up in the air at the moment.
"The plan would include many changes although the existing petrol station would remain in its current location with the addition of a possible new car wash.
"The Harry Tuffins building is part of a mixed use site and is visually important in the town.
"This application not only has the potential to improve the supermarket but the whole site and will include large changes to the car park at the centre.
"An area currently used as an unloading bay could be utilised to allow the supermarket to expand into the open air and create a new garden centre selling plants and shrubs."
The Midcounties Co-operative took control of Harry Tuffins, which has its headquarters at Churchstoke in April.
It has stores in Craven Arms, Bishop's Castle, Ludlow, Knighton and Cleobury Mortimer.
No one from Midcounties Co-operative was available to comment on the development plans.
By Peter Finch