The short answer
Ignore the "was" price, look only at the price per unit on the shelf label, and ask whether you were buying it anyway.
- Find the unit price, the small figure in pence per 100g or per litre. It is the only comparable number on the shelf.
- Ignore the reference price. It tells you what the retailer chose to compare against.
- Ask whether you were buying it anyway. A discount on something you did not need is spending, not saving.
- Be wary of loyalty pricing. A member price is a normal price with a higher price for everyone else next to it.
What will ruin it
Shelf labels occasionally give unit prices in different units for competing products, per item against per 100g, which makes them look very different. Check the unit before comparing.
Why it works
Retail pricing is designed around the reference point you are given rather than the absolute price. The unit price is the only figure on the label that is not chosen for its psychological effect.
Tipking is general household information, not professional advice. Test anything on a hidden patch first. Full disclaimer.
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