The supermarket where Canberrans are getting the best prices

A review into supermarket prices found a basket of typical groceries sets an ACT shopper back an average $62.62, the cheapest among the states and territories.

Consumer advocacy group Choice sent mystery shoppers to 81 supermarkets across the country and gave them a list of 14 common grocery items.

In Canberra, the mystery shoppers found the basket of groceries was cheapest at Aldi at $50.82, compared with $68.25 at Woolworths and $68.80 at Coles.

Choice's first quarterly report into supermarket prices was funded by the federal government, as part of its crackdown on major supermarkets.

Choice's undercover shoppers were given a shopping list of 14 common groceries, including fresh produce and packaged items.

The shopping list:

The shoppers were sent to three different supermarkets in 27 locations. In the three areas where no Aldi was available, the shoppers went to IGA instead.

They recorded regular prices as well as special discounted prices.

The average ACT grocery shop came out at $62.62 without specials and $61.21 with specials.

There were only marginal differences between most of the states and territories, with Queensland grocery baskets coming in as the second cheapest at $62.82 without specials.

The cost of a shop jumped up for Tasmanian and Northern Territory households, where the grocery bill without specials came in at $68.90 and $68.62 respectively.

Choice noted the higher costs in Tasmania and the Northern Territory were mainly due to the limited options, with no Aldi stores in those jurisdictions.

Supply in the Northern Territory was also impacted by Tropical Cyclone Megan at the time of the survey.

Choice CEO Ashley de Silva said where people lived made a difference when it came to the cost of groceries.

"Outside of the Northern Territory and Tasmania, Western Australians are paying the most on average for their groceries - around a dollar more for this basket of items than people in other parts of the country pay," he said.

The federal government gave $1.1 million to Choice to conduct quarterly reports into grocery pricing for three years.

It came at the same time the government announced a year-long inquiry into the supermarket industry.

Assistant Minister for Competition, Charities and Treasury Andrew Leigh said the research would empower households to seek cheaper prices at the supermarket.

"Helping shoppers find the best deal makes the family budget stretch further and puts more competitive pressure on the supermarkets," he said.

"Australia's supermarket sector is one of the most concentrated in the world, and it's only fair that big supermarket chains get proper scrutiny to ensure that they're doing the right thing by their customers."