Co-op is on average 49.6% dearer than Aldi

We compare the price per kilo, per litre or per item, so pack sizes do not distort the result. Items sold by the piece are only compared with a similar number of pieces. Own-label means each shop's own brands, whatever their name; premium ranges rarely pass our matching check, so these are mostly standard lines. Prices as of 31 August 2026; where a cheaper promotion was running, we use that price.

For each spending category we average the price differences of the products both shops sell, then combine the categories by their share of household spending. The ranking on the Price Monitor page compares all shops at once, through every other shop as well, so it can differ from this two-shop figure; for these two shops the ranking gives Co-op 43.9% dearer. Categories with fewer than 10 products both shops sell: sugar, jam, confectionery: 5 products, 7% of the weight, fish: 1 product, 4% of the weight. They count at their full share of household spending, like every category, so they can move the figure more than their few products suggest.