Understanding Best Before and Use By Dates

Two different kinds of date

Food packs often carry a date, but the dates do not all mean the same thing. The most important distinction is between a date about safety and a date about quality. Labelling rules vary between countries, so check the rules where you live; the descriptions below follow the commonly used UK and EU approach.

• Use by: a safety date. It appears on foods that can become unsafe to eat over a short time, typically chilled items such as fresh meat, fish, ready meals and some dairy products. After the use by date, the food should not be eaten, even if it looks and smells fine, because harmful bacteria cannot always be detected by sight or smell.
• Best before: a quality date. It tells you how long the manufacturer expects the food to be at its best in flavour, texture or appearance. After this date, the food is not necessarily unsafe, but it may be less good. It is mainly used for dried, tinned, frozen and long-life foods.

Some products also show “display until” or “sell by” dates. These are mainly for shop stock control, not for you, and are not a safety limit. In some countries, other wording such as “expires on” or “packed on” is used, so it is worth learning the local rules.

Why the difference matters for waste

A lot of edible food is thrown away because people read a quality date as a safety date. Biscuits, rice, pasta, tinned food and many other foods are generally fine after their best before date, though they may be a little stale or less flavourful. Throwing them out means wasting all the resources used to make them, so learning the difference is one of the simplest ways to cut food waste.

The reverse also matters: treating a use by date casually can be risky. Do not eat food past its use by date, and do not rely on smelling it. Bacteria that cause food poisoning may not change how the food looks or smells.

Following the use by date

A few practical points keep use by foods safe:

1. Follow the storage instructions on the pack. The date only applies if the food is stored as directed, for example in the fridge.
2. Once opened, a pack may have a shorter life. Look for wording such as “eat within three days of opening”, and follow it.
3. Keep your fridge cold enough, generally at or below about 5°C (41°F). A thermometer can show if yours is too warm.
4. You can freeze food up to its use by date, and then use it after defrosting. Follow the freezing and defrosting directions on the label, and use the food within a short time after thawing.
5. Cook it or freeze it by the use by date if you will not eat it in time. If you plan your meals, you can schedule use by items early in the week.

Some people are more vulnerable to food-borne illness, including pregnant people, older adults, very young children and anyone with a weakened immune system. For these groups, being stricter with dates and storage is sensible, and health professionals can give specific advice.

Judging best before foods

For foods with a best before date, using your senses is generally reasonable. Look, smell and taste a small amount. Signs of problems include mould, an off smell, an unusual colour or texture, and swollen or damaged packaging. The right response depends on the food.

• Dry foods such as pasta, rice, flour, cereals and dried pulses often last well beyond the date if kept dry and sealed. Check for moisture, insects or a stale smell. Flour and wholegrain products can go rancid over time.
• Tinned food is generally fine if the can is undamaged. Discard cans that are bulging, leaking or badly dented along a seam.
• Frozen food stays safe if kept frozen, though quality declines over time. A best before date on frozen goods is about quality.
• Eggs in some countries carry a best before date. Practices differ between countries, so follow the guidance for where you live, and cook eggs thoroughly if they are near or past the date, especially for vulnerable people.
• Fruit and vegetables often carry a best before date or none at all. Judging by appearance and feel is usual; for more on helping them last, see produce storage.

Bread, cakes and other bakery items generally show signs of mould before they become dangerous, but mould on soft foods can spread beyond what you see, so discard these if mouldy. Do not simply cut it off from bread.

Leftovers and cooked food

Leftovers have no printed date, so you need a routine:

• Cool cooked food quickly and refrigerate it, ideally within about two hours.
• Store in a covered container in the fridge, and eat within a few days. A common guideline is up to about two days for most dishes and a little longer for others, but check the guidance used where you live.
• Reheat until it is steaming hot all the way through, and do not reheat the same food repeatedly.
• Rice needs special care. Cooked rice left at room temperature can allow bacteria to grow, so cool it rapidly and refrigerate it promptly.
• Label containers with the date you cooked the food. This takes the guesswork out later.
• When in doubt, throw it out. A little waste is better than risking illness, and the risk is much higher for leftovers that were left out for hours.

Freezing is a good way to keep leftovers longer. Freeze portions soon after cooking and label them with the contents and date.

Using this to waste less

Knowing the label rules works best with a few supporting habits. Check dates when you shop and put newer items behind older ones at home. Plan meals around what needs using first, as described in meal planning. Keep a “use first” area in the fridge. Buy sensible quantities, since a bulk offer is only a bargain if you can eat it. A tidy, cold fridge also keeps food fresher, and the habits behind fridge efficiency help here.

These are general guidelines, not medical or legal advice. If you are unsure about a particular food, the manufacturer or your local food safety authority can provide specific guidance.