Tailem Bend and Meningie's supermarkets could be at risk of closure if planned changes to land tax are approved, their owner says.
Eudunda Farmers managing director Alistair Schuller, whose company owns the Foodland stores and 22 others across South Australia, has come out swinging against the changes proposed by the state government.
"We are looking at an increase of around 500 per cent in our land tax bill," Mr Schuller said, adding that the amount would be enough to threaten the sustainability of the company's operations.
The amount of revenue Eudunda Farmers received from country SA was not growing, he said, and the money would have to come from somewhere.
"If we are forced to close, it is local people who will lose out," he said.
"If we are forced to sell our stores, who will buy them?
"Where is the concern for country residents and country jobs?"
Labor opposition MP Clare Scriven suggested some towns would not be able to retain their populations if the only shop in town closed.
"Some of these towns may not survive," she said.
"Even those towns with more than one supermarket will have reduced competition if one store closes, which is a poor outcome for local people, as well as the loss of local jobs."
She argued that the state government should have modelled the effect the changes would have on regional communities.
The changes, first proposed in the state budget in June, would make it more difficult for owners of multiple properties to minimise the amount of tax they would pay by using complex ownership structures.
They would also reduce the tax rate paid by high-end land owners.
Treasurer Rob Lucas originally characterised the present tax arrangement as an unfair loophole.
But the government has since been forced to modify its legislation several times to appease affected property owners.
Mr Lucas said a fortnight ago the latest version would reduce the amount of land tax collected by the government by $90 million, and that more individuals and companies than originally estimated would benefit from the changes.
Business SA has argued that the ongoing uncertainty around the tax has contributed to record low levels of business confidence in the state.