Smart shopping

Updated 9 April 2026

How to compare supermarket prices in Australia

Three ways to compare grocery prices: unit pricing, price history, and cross-store comparison. Stop overpaying at Coles and Woolworths.

The three numbers you need.

Most Australians compare prices only on the sticker. That is the first mistake. There are three different ways to look at the cost of a product, and each one tells a different story. You need all three to actually know whether you are getting a good deal.

1. The unit price (per kg, per litre, per 100g).

The unit price is printed on every shelf label in Australia. It is the law since 2009. It is also nearly invisible because most people do not look for it.

The unit price strips away the packaging and tells you what you are actually paying per standard measure. A 2kg bag of rice at $6.00 looks cheaper than a 1kg bag at $3.50. But the unit price shows the opposite: $3.00/kg versus $3.50/kg. The smaller bag is more expensive per kilo, and the sticker price lied.

The rule "bigger is cheaper" breaks down constantly. The 1L bottle of Coles olive oil costs 14% more per litre than the 500mL bottle. The Weet-Bix "family pack" is more expensive per 100g than the mid-size box. The multipack yoghurt costs 50% more per gram than buying the tub. Without checking the unit price, you would have no way to know.

Check the unit price before you grab the pack you always grab. It takes three seconds and it saves money on every shop.

2. The cross-store price (same product, different retailer).

Coles and Woolworths charge roughly double what ALDI charges on chicken breast. Harris Farm milk is nearly half the price of Coles and Woolworths. These gaps are not promotional. They are the everyday shelf price, and they are the single biggest opportunity to save money.

Comparing a single item across four stores manually takes 20 minutes. Comparing your whole trolley takes hours. Most families never do it, which means they are leaving money on the table every week.

On these six products alone, ALDI saves you $10+ compared to Woolworths. If you buy these items every week, that is $500+ a year. And this is just six of 74,000+ products.

3. The price history (is this week's "special" actually cheap?).

A product on the shelf is marked "special" at $3.99. That sounds good. But was it $3.50 three months ago? Was it $3.99 every week for the last month, just without the red sticker? The "special" is not a deal if you are buying at the same price you paid six weeks ago.

Coles and Woolworths use high-low pricing. A product cycles between a "regular" price and a "special" price on a predictable pattern. The cycle might be four weeks high, two weeks low, repeat. Over a year, you end up paying the average. The question is not whether the product is on special today. The question is whether today's special price is lower than the product normally cycles to.

Pinch found that 2,308 products are currently on repeating cycles where even the cycle low is 15% above the historical price. Another 230 products are marked "on special" at prices higher than what you were paying a year ago. That is shrinkflation or hi-lo pricing tricking you into thinking you are getting a deal.

To see whether a special is real, you need the last 52 weeks of price data for that specific product. Most customers never see that data. Retailers have no reason to show it to you.

Why the sticker price is not enough.

Most people compare only on sticker price. That is one number. It is also the one number that is easiest to manipulate.

Different pack sizes hide real costs.

Retailers often change the pack size while keeping the sticker price the same. A 175g yoghurt pack shrinks to 150g, still $4.50. The sticker price says it is the same deal. The unit price reveals the 16.7% price increase. This happens constantly, especially with private-label products during "specials."

Specials are not always cheaper than everyday prices at other stores.

You see a "special" at Coles at $3.99 for butter. It feels like a deal because the word "special" is on the shelf tag. But ALDI's everyday price on the same product is $3.50. You are not saving money by buying the "special." You are paying a premium for the convenience of shopping at Coles.

This happens because different retailers position themselves differently. Coles and Woolworths run specials on products they know you buy every week, to get you in the door. Then they charge full price on everything else. ALDI competes on everyday price, not on specials. For a customer who shops at Coles, the "special" feels like a win. For a customer who knows ALDI prices, it is a loss.

The catalogue trap.

Both major supermarkets publish glossy weekly catalogues full of highlighted specials. The psychology is obvious: you see the red box, you think you are saving money, you fill your trolley. In reality, the items in the catalogue are often the ones that benefit the retailer most, not the ones that benefit you.

The ACCC's Supermarkets Inquiry (February 2025) found that supermarket discounting is carefully targeted to keep customers loyal while maximising profit on everything else. You are not seeing the products that are actually cheap. You are seeing the products the retailer chose to highlight.

How to compare systematically.

Build your shopping list with unit prices visible.

Before you go to the supermarket, add every item you need to a list. For each item, look up the unit price at all four retailers. Do not compare just sticker prices. Compare the cost per kg or per litre. Buy from whichever store has the lowest unit price for that specific product.

You do not need to shop at one store. You can buy milk at Harris Farm, chicken at ALDI, and bread at Coles. Most families do not do this because it requires checking four different places. But the savings are real.

Check the 52-week price history before buying "specials."

If something is marked special, check the historical price. If the special price is not lower than the product normally cycles to, skip it. Buy next week instead, when you have a genuine low price. Or buy from a different retailer at their everyday price.

This requires data most people do not have. Supermarkets do not publish price history. You have to track it yourself, or use a tool that already has.

Skip the catalogue, check unit prices instead.

The weekly catalogue is designed to capture your attention, not to show you the best deals. The best deals are often the products that are not highlighted at all, just sitting on the shelf at their everyday low price.

What Pinch automates.

Comparing prices properly means:

• Checking the unit price for every product at every retailer (automated by Pinch).
• Comparing the same product across four stores (automated by Pinch).
• Checking 52 weeks of price history to spot real deals (automated by Pinch).

Without this data, comparing prices is so time-consuming that most families just pick one store and stick with it. With it, you can build a weekly shopping list, see the total cost at each store, and pick the cheapest option before you leave home.

The myth of loyalty programs.

Coles has Flybuys. Woolworths has Everyday Rewards. Both offer points on purchases, which sounds like a discount. The math does not work.

Flybuys typically gives 1 point per dollar spent. 2,000 points converts to $10. That is 0.5% discount. You could achieve the same discount by walking to ALDI instead, which charges 15-25% less on many products.

The loyalty programs exist to lock you into one store, so you never compare prices. You accumulate points slowly, feel invested in the retailer, and keep shopping there even though the everyday prices are higher. The program makes sense for the retailer. It does not make sense for you.

What the data shows.

Pinch has tracked 74,000+ Australian grocery products for over a year across four major retailers. Here is what the data reveals about how Australians should actually compare prices:

• Unit prices are essential. Without checking unit price, you cannot answer "is this a good deal?" You can only answer "is this cheaper than the other size of the same brand?"
• Cross-store gaps are massive. The same chicken breast costs $7.85/kg at ALDI, $15.00/kg at Coles, $14.90/kg at Woolworths. That is nearly 2x the price for an identical product.
• Specials are not random. Retailers put specials on products you buy every week, at prices designed to feel like savings without actually undercutting their competitors. The real cheap products are the ones not on special.
• Hi-lo pricing is the default. Most products at Coles and Woolworths cycle between a high price and a low price on a repeating pattern. The cycle is predictable once you see the data. The "special" is often just the return to the regular cycle low, not a genuine discount below normal.

Sources

• Pinch price tracking database (74,000+ products across Coles, Woolworths, ALDI, Harris Farm)
• Unit Pricing Code of Conduct, Australian Government Competition and Consumer Act 2010
• ACCC Supermarkets Inquiry Final Report, February 2025
• Price data current as of 9 May 2026