How to check if a seller has sold you the correct amount, and what to do if it's a short measure.

Your rights

The Weights and Measures Act sets out rules for selling goods by quantity in New Zealand. It’s there to make sure businesses sell correct quantities, and you get what you pay for. Goods sold by weight, volume, length or number must be:

  • accurately weighed, measured or counted
  • clearly labeled with the correct net quantity.

Goods bought by weight or measure must be sold to you by net weight or measure. This means the weight of any packaging must be excluded from the weight or measure statement.

Examples of goods sold by weight or measure include:

  • coffee beans sold by kilo
  • firewood sold by cubic metre
  • potting mix sold by litre
  • railway sleepers sold by number.

Trade measurements - for consumers(external link) — Trading Standards

Measuring rules for different types of products

Click on a heading to find out more about buying by weight, measure or number.

If things go wrong

If the quantity is not marked on a package, you can ask for a written statement of the goods.

If you think you have been sold a short amount, you can:

  • Ask the seller to re-weigh or measure the goods in front of you.
  • Tell the seller you believe they have sold you a short weight or measure.
  • Check to see whether their scale or the petrol pump has a current certificate of accuracy — you can rely on scales and pumps that have a current certificate.

Complain to Trading Standards

If you can't resolve it with the seller — or you think a seller's measuring equipment doesn't meet the rules — you can report it to Trading Standards.

Trading Standards can't act on your behalf about your specific issue. But reports from the public help it identify sellers, industries or equipment suspected of regularly breaking the rules. Trading Standards can:

  • seize short weight or measure goods
  • seize inaccurate weighing or measuring equipment
  • fine the seller if they have breached the Weights and Measures Act.

Trade measurement - Making a complaint(external link) — Trading Standards


Example — Amount seems less than ordered

Janet orders three cubic metres of pine firewood, but when it arrives she notices the amount seems to be less than she had delivered last year. She talks to the seller, who says it is more or less three cubic metres but that he has not checked. He agrees to check the amount delivered against the approved volume measure.

Example — Petrol pump bill seems too high

John fills up his car with 100 litres, but at the till he is charged for 102 litres. John thinks he might have been charged for more petrol than he received. The attendant explains petrol pumps are very precise, and fuel tanks can hold slightly more or less than they are meant to. John is satisfied he received all the petrol he paid for.