Unit Pricing in Australian Supermarkets: How to Read It and Use It

Unit pricing shows the real cost per 100g or 100ml, making it easy to compare different sizes and brands. Here's how to read it and use it to save money.

Unit pricing is the cost per standard measure — per 100g, per kg, per 100ml or per litre — and it's the most honest number in a supermarket for comparing value across different sizes, brands, and "specials." Australian law requires large supermarkets to display it on shelf labels. The shelf price tells you what something costs; the unit price tells you whether it's good value — and on staples, home brands typically run 20–40% cheaper per unit than national brands.

Here's how to find it, read it, and use it to get the best value consistently.

Where to Find the Unit Price

The unit price appears on the shelf label below the item, usually in smaller type than the main price. It's typically shown as:

• $X.XX per 100g — for most packaged dry goods (biscuits, cereal, pasta, mince)
• $X.XX per kg — for bulk or heavier items and most fresh produce
• $X.XX per 100ml or per litre — for liquids (milk, juice, oil, cleaning products)
• $X.XX per unit — for items like eggs or toilet paper rolls

If the label is missing or hard to read, you can calculate it yourself: divide the total price by the weight or volume. A 600g pack at $5.40 is $0.90 per 100g. Simple.

Comparing Like for Like

The key rule: always compare the same unit. This sounds obvious but it's easy to slip up.

If one product shows a price per 100g and another shows per kg, convert one before comparing. Multiply the per-100g price by 10 to get the per-kg equivalent.

If one product is measured by weight and another by volume (this happens with some juices and beverages), the comparison is less straightforward — you'd need to account for density. In practice, the simplest approach is to only compare products displayed in the same unit.

Where Unit Pricing Actually Saves You Money

Different sizes of the same product

This is the most common application. A smaller pack isn't always cheaper per unit — and a bigger pack isn't always better value either. The only way to know is to check.

Example: A 500g tin of tomatoes at $1.80 costs $0.36 per 100g. A 400g tin at $1.20 costs $0.30 per 100g. The smaller tin is better value per unit, even though it costs less overall and is the smaller size.

Branded vs. home brand

Home brand products are almost always cheaper per unit than the equivalent national brand. On staples — flour, pasta, rice, tinned goods, sugar, cleaning products, milk — the difference is typically 20–40%. For these categories, the unit price makes the comparison immediate and concrete. Swapping to home brands on these everyday items is one of the simplest ways to cut your weekly grocery bill.

Products "on special"

A deal sticker doesn't automatically mean best value. A "special" on a premium brand might bring it down to the same unit price as a home brand at full price — or even leave it more expensive. Always check the unit price of the "special" item against comparable alternatives on the same shelf. If you want to dig deeper into how genuine supermarket discounts work, see our guide to supermarket specials in Australia.

Woolworths and Coles house brands vs. each other

Both chains have house brand ranges at different price tiers. Unit pricing lets you compare these directly without getting confused by different pack sizes.

The Challenge With Promotional Deals

Multi-buy deals ("2 for $X", "Buy 3, save $2", "Buy One Get One Free") present a specific challenge: the displayed unit price often reflects the single-item price, not the effective unit price when you take the deal.

To get the real unit price on a multi-buy deal, calculate it yourself:

Example: A 250g pasta is $2.40 normally ($0.96/100g). The deal is "2 for $4." You're getting 500g for $4, so the real unit price is $0.80/100g — a genuine saving.

Example: A cleaning spray is "3 for $12." Each is $4.20 normally ($0.42/100ml for 1L bottles). Three units = 3L for $12, or $0.40/100ml. Modest saving, but only if you'll actually use three bottles before they expire.

The questions to ask before taking a multi-buy deal:

• What's the effective unit price?
• Is that actually cheaper than a different size or brand at full price?
• Will I use all of it before it goes off or gets wasted?

What About Fresh Produce?

Fresh produce is almost always priced per kg, which makes unit price comparison straightforward — the displayed price is the unit price. The complication is quality variation within a category: loose vs. pre-packed produce, or premium vs. standard grade, may be priced differently for reasons beyond simple weight.

One thing worth noting: some produce has natural waste (husks, skins, seeds) that affects the usable yield per kilogram. Pre-cut or prepared produce eliminates that waste but typically costs more per kg. Whether the premium is worth it depends on your situation.

Using Unit Pricing Across Different Stores

Unit pricing is most useful when comparing products within the same store. Comparing unit prices between Coles and Woolworths for the same product is also valid — but you'd need to check both stores' prices, either in-person or online.

Grocero does this work for you by showing prices across Coles, Woolworths, and other Australian supermarkets in one place. Rather than checking each store's website or app separately, you can see which store has the lowest price on each item on your list. This effectively extends unit price comparison across stores without any manual calculation.

For a broader look at which stores are consistently cheapest across different categories, see our Aldi vs Coles vs Woolworths comparison and our guide to the cheapest supermarket in Australia.

Unit Pricing Regulations in Australia

Australian law requires large supermarkets to display unit prices on shelf labels. The requirement applies to Coles, Woolworths, Aldi, and IGA stores above a certain size. Smaller independent grocers and specialty food shops are generally not required to display unit prices, though many do voluntarily.

The regulations cover most packaged grocery items. Fresh produce, bakery items sold loose, and some prepared foods may be exempt or handled differently.

If a unit price is missing or appears to be inaccurate, you can ask store staff or report it to the ACCC.

Frequently Asked Questions About Unit Pricing

What is unit pricing and why does it matter?

Unit pricing shows the cost per standard measure — per 100g, per kg, per 100ml, or per litre. It matters because products come in different sizes and pack configurations that make the sticker price misleading as a value comparison. The unit price is the honest, apples-to-apples number.

Where do I find the unit price in a supermarket?

On the shelf label, usually in smaller type below the main price. It shows up as a cost per 100g, per kg, per 100ml, or per litre depending on the product type. If it's not visible or seems wrong, divide the total price by the weight or volume to calculate it yourself.

Is bigger always cheaper per unit?

No. Bulk sizes are often cheaper per unit, but not always — particularly when a smaller size is on special. Always check the unit price rather than assuming a larger pack is better value.

How do I find the real unit price on a multi-buy deal?

Calculate it yourself: total price divided by total quantity. For example, "3 for $9" on 500ml bottles gives you 1.5 litres for $9, or $0.60 per 100ml. Compare that against the unit price of alternative products to see if it's actually the best deal on the shelf.

Are home brand products genuinely cheaper per unit?

Yes, almost always on staples. The difference is typically 20–40% on flour, pasta, rice, canned goods, dairy, cleaning products, and similar categories. Quality has improved significantly across both major chains' private label ranges in recent years.

Do unit prices account for promotional deals?

Not automatically. The displayed unit price usually reflects the single-item price, not the effective unit price when a multi-buy deal is applied. You need to calculate the effective unit price yourself for deals like "2 for $X" or "Buy One Get One Free."

Are supermarkets required to show unit prices in Australia?

Yes, for large supermarkets. Australian regulations require Coles, Woolworths, Aldi, and IGA stores above a certain size to display unit prices on shelf labels. Smaller independent grocers are generally not required to comply, though many do.

How can I compare unit prices between different stores?

You can check each store's website or app individually, or use a price comparison tool like Grocero that shows prices across Coles, Woolworths, and other Australian supermarkets in one place. This saves you from having to open and cross-reference multiple apps.

Why does unit pricing seem inconsistent across different promotions?

Because it often is. Stores typically display the single-item unit price even when a multi-buy deal changes the effective cost per unit. This isn't necessarily deceptive — it reflects the complexity of displaying a single unit price for a deal that only applies when you buy a certain quantity — but it does mean you need to do the maths yourself for promotional items.

Does unit pricing work the same way at Aldi?

Yes. Aldi displays unit prices on shelf labels in the same way as Coles and Woolworths. Since Aldi's range is smaller and more focused on private-label products, you'll typically have fewer options to compare within the same category — but the unit price remains the right way to assess value, particularly when comparing across stores.