Weights and measures

Goods sold by weight or measure must be sold in metric quantities. For example:

• if you sell by weight, you use kilograms and grams instead of pounds and ounces
• if you sell by volume, you use litres instead of pints, or cubic metres instead of cubic feet
• if you sell by length, you use metres instead of feet and inches

You must mark packaged goods with the metric measure. If you want, you can also show the imperial measure as well. But it must not be more prominent than the metric measure.

There are no restrictions which limit the range of sizes pre-packaged goods (except for wines and spirits) can be packed in. Aerosol products can be packed by weight and volume. Even though goods can now be packed in any size, you can continue to use traditional standard pack sizes if you wish.

Exceptions

There are only a few exceptions to the metric unit rules. The following can be sold by imperial units:

• pints of draught beer and cider
• pints of milk in returnable containers
• troy ounces of precious metals 

Trading Standards

Northern Ireland Trading Standards officers can advise you. They also make occasional checks to make sure you're following the rules.