The nation's two biggest supermarket chains have declared they will spare customers any carbon tax pain on Sunday, ruling out overnight price rises.
Coles and Woolworths said they would closely scrutinise claims by suppliers for price rises attributed to the carbon tax, while recent efforts to save energy in stores would allow them to absorb the cost of their own rising power bills.
Treasury modelling estimated that the carbon tax would push up the overall cost of living by 0.7 per cent. The average increase in food is estimated to be less than $1 a week.
Coles communications head Jon Church said customers expected the supermarket chain to shield them from the effect of the carbon tax as much as possible.
"We're not just going to automatically pass on the cost to the consumer but we're going to be looking to see that cost is justified and that suppliers have been doing, as we have, what they can to reduce their exposure to the carbon tax," he said. "We're not seeing signals of suppliers expressing any concerns over cost increases so I think it will be managed well for consumers."
Woolworths also said shelf prices would not change on Sunday.
"We have had requests for price increases from three service suppliers and no requests from retail suppliers," a spokeswoman said.
"Regulators have said that the carbon tax will impact the cost of some inputs in the future, like electricity, and we will continue to monitor this closely on behalf of our customers and shareholders."
WA Independent Grocers Association president John Cummings said it would take about six months before customers noticed price changes.
Coles and Woolworths said they had invested heavily in making their stores and supply chain more energy efficient.
Woolworths has a target of reducing emissions from stores by 40 per cent by 2015.
The Australian Competition and Consumer Commission has warned retailers about using a flyer produced by the Opposition that it is encouraging businesses to put up in their stores. The flyer, focused on sectors such as bakeries, butchers and dry cleaners, tells customers the carbon tax will push up energy prices that will flow through to products.
The ACCC said while there was nothing wrong with the flyer, those using it would have to be able to account for price rises they linked to the carbon price.
Assistant Treasurer David Bradbury said firms that could not back up claims of carbon tax price rises faced fines of up to $1.1 million. <div class="endnote">