Cleaning and personal-care prices today: dish liquid, laundry powder, and shampoo

Price per litre, not price per bottle

Cleaning products have the grocery problem, harder: one brand sells dish liquid in 750ml, 1 litre, 3.75 and 4 litres, and all of them show up in a list as "dish liquid". The big bottle almost always has a lower per-litre price — but not always, and not by the same margin in every shop, which is exactly where comparing prices pays. For tablets and powder, count and weight play the role volume plays for liquid.

Buying notes for this category

• Authenticity: for imported detergents, genuine and lookalike stock are two separate prices sitting side by side in a raw list.
• Value packs and promotions: a multipack is usually cheaper, but work out the unit price yourself.
• Concentration: concentrated liquids are smaller and go further; price per wash is not price per litre.
• For household use a carton is usually better value than single units, and it is the same product.

If a number is unusually far below the market it is normally either lookalike stock or an old price; how to spot a fake discount shows the patterns.

To price a full monthly shop or a shop's order, the bulk price inquiry guide is the quickest route.