I don’t want to be seen to be harping on, but how long do we have to give supermarkets to up their game in displaying unit pricing before they’re regulated?

Under instruction from friends, who complained bitterly about my lack of any decent olive oil (they were helping me organise a wee party), I tottered off to the supermarket to get some. Knowing how dear the real oil is, I wanted to compare prices. What a shambles. In the end I just bought the most expensive.

This week I checked the oils section again to see if my previous visit was a one-off. It wasn’t. Some oils displayed no unit prices and others had different measures making it impossible to compare.

Unit pricing is supposed to be about making it easier to compare oils with oils. Labels should show the cost per unit of measure – for example, per 100g. This enables you to tell whether a bigger bottle of oil is better value than a smaller one.

Both supermarket chains have voluntarily introduced unit pricing (no doubt under pressure of having it enforced). But it’s a hit and miss affair. Unit prices are usually displayed much smaller than the retail price and they don’t make it that easy to compare like with like.

A trial by the Queensland University of Technology found shoppers armed with unit-pricing information saved on average 11 percent of their grocery bill. Perhaps that’s why our chains are making it so difficult.

Unit pricing is mandatory in Australia, in the EU and some states in the USA. Queensland study co-ordinator Dr Gary Mortimer said it was particularly useful for comparing basic consumables, which make up the bulk of the weekly grocery spend. But see the picture on unit pricing of milk taken at New World Thorndon in Wellington this week.

Consumer has been saying for years supermarkets need to make unit prices more prominent and reduce their use of different measures. They should also be displaying unit pricing online and in print ads.

If they continue to use such poor practices, they should be regulated. If you see poor displays of unit pricing or no unit pricing let us know – send us a pic with details of where you snapped it or post it on our Facebook page.

About the author:

Sue Chetwin has been our Chief Executive since April 2007 after more than 25 years in print journalism. She was formerly the Editor of Sunday News, Sunday Star Times and the Herald on Sunday. She says there are strong parallels between consumer advocacy and journalism.

Sue oversees all of Consumer’s operations and is also the public face of the organisation. Sue is a director of the Banking Ombudsman Scheme, an alternate on the Electricity and Gas Complaints Commission and a member of the Electricity Authority Retail Advisory group.