Aldi. On the government-funded CHOICE basket survey published in June 2026, a 16-item shop cost $68.60 at Aldi, against $77.53 at Woolworths, $78.58 at Coles and $91.65 at IGA.
Aldi won the quarter before that too. It is also a less useful answer than it sounds — because the survey measures one basket of 16 products, and you are not buying that basket.
The numbers, and where they come from
CHOICE runs a quarterly supermarket basket survey funded by the federal government, at $1.1 million over three years. Undercover shoppers priced the same 16 products — eight staples and eight seasonal items — at 104 supermarkets across 27 locations. The fieldwork was done in March 2026 and published on 25 June 2026.
| Supermarket | Basket, no specials | Basket, with specials | What specials saved |
|---|---|---|---|
| Aldi | $68.60 | $68.60 | $0.00 |
| Woolworths | $77.53 | $76.82 | $0.71 |
| Coles | $78.58 | $78.50 | $0.08 |
| IGA | $91.65 | $86.33 | $5.32 |
Prices are CHOICE's, collected in March 2026, and will have moved since.
Three things stand out, and the arithmetic below is ours, done on CHOICE's published figures.
The gap to Aldi is real but not enormous. $8.93 against Woolworths and $9.98 against Coles — about 11.5% and 12.7% of those baskets. Worth having, and smaller than the headline gap suggested by comparisons that pick their items.
Coles and Woolworths are effectively the same shop, on price. $1.05 apart without specials, $1.68 with them. If you are choosing between those two on price alone, you are choosing between almost nothing.
Specials did not move Aldi at all. Aldi's basket cost the same either way, while IGA's dropped $5.32 — and the same thing happened in the December quarter, where Aldi's total was identical with and without specials. Aldi's model is a low shelf price rather than a high one discounted; the big two put more of their movement into promotions, which is precisely the part that changes week to week.
Why "which supermarket is cheapest" is the wrong question
The survey answers a narrow question honestly. Applied to your shop, four things get in the way.
It is 16 items, and your trolley is not. A basket that fits on one receipt line cannot tell you what a fortnight of your own groceries costs. The winner on 16 products is not automatically the winner on your 60.
The baskets are not brand-for-brand. CHOICE is explicit about this: the Coles and Woolworths baskets held three name-brand products — Tim Tams, Kleenex tissues and Chicken Tonight sauce — while Aldi's held one, and IGA's held five, "because its home-brand ranges aren't as extensive". That is unavoidable when Aldi mostly sells its own labels, but it means part of the gap is an own-brand product measured against a branded one rather than the same product at two prices. If you buy particular brands, your gap will be different.
Specials are where the big two actually compete. Aldi's price was static. Woolworths and Coles move constantly, and a well-timed shop closes some of the distance on the items that happen to be down that week. A quarterly snapshot cannot capture that, and neither can a memory of what something cost last month.
There may not be an Aldi near you. Aldi holds nine per cent of the market, and took more than 20 years to get there. Which chain is cheapest is academic if the nearest one is a half-hour drive, and "shop at the cheapest supermarket" is advice that quietly assumes you can.
What actually decides your grocery bill
Not the chain. The prices of the specific things you put in the trolley, in the week you buy them.
Our own records make that concrete. Take every identical product we hold a price for at both Coles and Woolworths, and the two chains charge exactly the same on close to half of them.
10,988 identical products priced at both Coles and Woolworths.
- Same price at both
- 46.9%
- Cheaper at Woolworths
- 28.2%
- Cheaper at Coles
- 24.9%
Where the two differ, the middle gap is $2.00 — about 28.6% of the dearer price. Across the whole set, taking whichever chain is cheaper on each product comes to 9.7% less than buying all of them at either one.
And most of that difference is a promotion rather than a different shelf price: 85.1% of the products where the two chains differ have at least one side on special.
Grovena’s own data, updated with each price collection — figures as at 27 September 2026. Current prices including anything on special that day, so the split moves week to week. The 9.7% is what the gap adds up to across every product in this set, not a saving on a real shop: collecting it would mean buying all of them and shopping both chains. Online prices, so in-store tickets and state-based variations sit outside it.
Read that carefully, because it is not the same claim as the CHOICE result above. CHOICE compared a 16-item basket across four chains, much of it own-brand, and Aldi won it. This compares the same product at two chains — the identical tin, the identical box. On that question there is no winner worth naming: they match on nearly half, and split the rest almost evenly.
Which is the point. Picking a chain and staying loyal to it optimises the one variable that barely moves. The gap that does exist sits at the level of individual products, in the week you happen to shop.
Grocery costs are still climbing — food and non-alcoholic beverages rose 3.3% in the year to June 2026, though that group is led by meals out and takeaway rather than supermarket shelves. And the ACCC found that Aldi, Coles and Woolworths are among the most profitable supermarket businesses among global peers, with average product margins rising over the past five financial years.
The practical move is not picking a team. It is checking, per item, which chain is cheaper for the things you actually buy — and comparing unit prices rather than shelf prices, so a 900g pack and a 1kg pack can be judged against each other. We ranked that move against every other piece of grocery-saving advice, with what each one is worth, in how to save money on groceries in Australia.
That is tedious to do by hand across three websites, which is the reason most people never do it. Put the three chains side by side — Grovena puts the prices it has matched for a product on the same card, showing the unit price alongside each one wherever the retailer publishes it. Where the catalogues do not line up, a card carries two rather than three. It is free and needs no account.
The regulator thinks this should be easier too
The ACCC's supermarkets inquiry recommended that the largest chains be required to publish their prices online, and that the very largest provide APIs "to third parties such as online price comparison tools".
The government agreed in principle in March 2025 and it remains under consideration. No chain publishes that open feed today, so the comparison still has to be assembled the hard way.
Common questions
Is Aldi always the cheapest?
On the total basket, in the surveys we looked at, yes. It also won the previous quarter's 20-item Christmas basket, at $72.41 against $98.98 at Woolworths and $100.04 at Coles. On any individual product, no — that is a different question, and it is the one that decides your bill.
Is Coles or Woolworths cheaper?
On the March 2026 basket, Woolworths, by $1.05 without specials and $1.68 with them. That is close enough that it will not hold for your basket in your week.
Can shopping the specials beat Aldi?
The survey does not show that. Specials took $0.71 off the Woolworths basket and $0.08 off the Coles one, against a gap of roughly $9. Specials matter most on the items you were going to buy anyway, which is a per-item question rather than a per-chain one.
Why is IGA more expensive?
IGA stores are independently owned franchises, so prices vary between locations far more than at the chains. CHOICE flags this as a limitation of comparing IGA as a single entity.
How often does this change?
CHOICE reports quarterly. Shelf prices change at least weekly — fresh produce more often again, and specials on their own cycle — which is why a survey tells you about a chain, and only a current price tells you about a product.
The short version
Aldi wins the basket, Coles and Woolworths are a coin toss, and IGA is dearer where it is not competing on convenience. But the survey measures 16 products in March, and your bill is made of your products this week.
And if the reason you came looking was to work out whether you are overspending, the basket survey cannot answer that either — we went through what Australians actually spend on groceries, and why no official figure exists.
See where your groceries are cheapest before you shop.