What do expiration dates really mean?

Dates on food packages are intended to ensure quality — not safety. They aren't required by law. (Some exceptions exist, such as infant formula.)

So what do they mean?

  • Sell by. This date tells the grocer how long to display the product for sale. You should buy the product before the date is past.
  • Best if used by (or before). This date is recommended for best flavor or quality. It is not a purchase or safety date.
  • Use by. This date indicates quality; there may be a decline in quality after this date. This date is set by the manufacturer.
  • Closed or coded dates. These are packing numbers for use by the manufacturer. These may be used in food recalls.

Rather than relying on these dates, make it a habit to use or freeze perishable food within a few days of purchase. Freezing ensures safety indefinitely. However, quality will decline over time.

Last Updated Dec 17, 2019

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