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Understand the Difference in Date Codes

Understand the Difference in Date Codes

What do the "sell by," "best if used by" or "use by" dates mean?

Have you ever purchased food and been confused about why some items have a “Use-By” date and some have a “Sell-By” date?  Here’s the quick run-down on what these different terms mean. 

Defining date codes

Open dating

  • “Sell-By” dates tell a store how long to display a product for sale. 
  • “Best if Used By (or Before)” dates indicate for best flavor or quality. It is not a purchase date or a safety date.
  • “Use-By” dates are the last date recommended to use the product while at peak quality. This is determined by the manufacturer of the product. 

Closed dating

  • Packing numbers for use by the manufacturer only. 

According to federal regulations, open dating is not required except on infant formula (“Use-By” dates are mandated for these products). Open dating on food products is the use of a calendar date to help determine how long a food is at its best quality. It is important to note that open dating is NOT a food safety date. After the date passes, a food product may not be at its best quality, but it should still be safe if properly handled and stored at proper temperatures. If you freeze a perishable item, it doesn’t matter what date is stamped on the product, because foods kept frozen are safe indefinitely. 

Canned products include a packing code (a series of numbers and/or letters) that enables tracking of a product for interstate commerce. This is an example of closed dating. This type of dating allows manufacturers to rotate their stock and to locate products in the event of a recall. These dates are NOT meant for consumers to interpret as “Use-By” dates. There is no book or website that explains the translations of the codes into dates since each manufacturer can use a unique coding system. Canned foods are safe to consume indefinitely as long as they are not exposed to freezing temperatures or temperatures above 90ºF (32.2ºC). 

If food you have purchased develops an off odor, flavor or appearance due to spoilage- you should not use it for quality reasons. If foods are mishandled (i.e. food left out for several hours at a picnic on a hot day), the product could potentially cause foodborne illness before the “Use-By” or “Best if Used By” date.  If you are ever unsure of the safety of a food product, it is always safer to dispose of the item. In other words, “when in doubt, throw it out!”