Best before, use by and expiry dates: what they really mean

Best before

The date of minimum durability: until this date the product keeps its quality, potency and properties when stored as directed. It is the right date for almost all food supplements (1169/2011 Art 24 and Annex X).

Use by

A safety date for highly perishable foods that could become dangerous quickly, such as fresh meat. Food past its use by date must not be sold. It is rarely relevant to supplements.

Expiry date

Used for medicines, not food. On a supplement it can blur the line with medicines, so use “best before” or “best before end” instead.

How to write the date

• Use “Best before” followed by a date that includes the day, or “Best before end” followed by the month and year or the year.
• For a durability of up to 3 months, give the day and month. For 3 to 18 months, the month and year. For more than 18 months, the year alone is enough.
• If the date is printed elsewhere, say where, for example “Best before end: see base”.
• Add any storage conditions the date depends on, for example “Store in a cool, dry place”.

Retest dates

The retest date on an ingredient's certificate of analysis is a quality control date for the raw material. Your product's best before should come from your own stability data, not the ingredient's retest date.