Use-by vs best-before: the label that costs you money

If you've ever stood at the fridge squinting at a carton, unsure whether "20 Aug" means bin it or it's probably fine, you're not alone. The two date labels on UK food mean very different things, and confusing them is one of the most common causes of household food waste.

Best-before is about quality

Best-before dates are about quality, not safety. After this date, food may be past its best (a little less crisp, less fresh), but it is generally still safe to eat. Think dried pasta, tinned goods, crisps, biscuits.

You can use your own judgement well beyond a best-before date. Bin food on a best-before date "just to be safe" and you're very likely throwing away perfectly good food.

Use-by is about safety

Use-by dates are about safety. This is the one that matters. Foods with a use-by date (fresh meat, fish, dairy, ready meals) should not be eaten after that date, even if they look and smell fine. Freezing right up to the use-by date is a great way to extend the window.

The simple rule: best-before = quality (use your senses), use-by = safety (don't risk it).

The bit the label doesn't tell you

Here's the catch. Both dates assume the packet is unopened. The moment you open that jar of sauce or carton of juice, the printed date is no longer the whole story. Now it's "use within 3–5 days of opening," and the clock starts from the day you opened it.

And that's the day almost nobody remembers.

That half-used jar at the back of the fridge? The date on the lid is meaningless once it's open. What matters is when you broke the seal. Without that, most of us do the same thing: throw it out to be safe.

The fix is stupidly simple

Write the date down. That's the entire trick. When you open something, note the day, and the "use within X days" instruction suddenly becomes useful instead of a guessing game.

That is the real gap. In a factory, how long something has been open is tracked to the hour. In your fridge, that information simply stops existing, and you are left guessing.

Source: Food Standards Agency — best before and use-by dates.