The 99-bed facility received planning permission earlier this year.
A proposed new midlands hospital is seeking to add an extra 50 beds to its facility.
John Flanagan Developments received planning permission for the new 99-bed hospital in Tullamore earlier this year.
It will be based on the Wellwood Healthcare Campus.
Construction was due to start this summer, but the developer has now approached Offaly County Council with plans to add at least 50 extra beds to the hospital.
The decision was made following a number of feasibility studies, which John Flanagan Developments says made it evident the facility will need to cater for more people.
Joint Managing Director of John Flanagan Developments, John Flanagan says:
"This new proposal will further enhance the healthcare needs of the greater midlands region."
Joint Managing Director, Dominic Doheny, says:
"Whilst our original plan was to commence building in the summer of 2023, further research into the healthcare needs both locally and nationally indicated that the increased size would allow for further supports to help address the deficit in such services in the midlands and greater midlands region.
This is an extremely important project for the country and the development needs to be in line with our growing population and needs to recognise future demands.
The hospital project and the hospital itself will provide a substantial economic boost to Tullamore and the region."