What do “sell by,” “best by/before,” “use by” and “expiration” mean?

Product dates falls into three main categories, two of which, unfortunately, overlap. Let’s see what each category actually means and why these may confuse the buyer.

1. “Sell by,” “pull by” or “purchase by”

This label tells the store manager that it’s time to stop selling the item. If you have a product at home that is approaching its “sell by” date, this does not mean that the product must be discarded. Dairy products often have a “sell by” date, but they may be good for several days after that date, depending upon the product and when it is opened. People who want to take home the freshest possible food can avoid buying something that’s near or at its “sell by” date. Those looking for bargains may choose to buy these same items if they’re discounted.

2. “Best by,” “best if used by,” or “better by,” and 3. “use by”

Here’s where things get fuzzy. Most customers who take note of these dates assume that “best by” gives them more leeway than “use by.” But here are the USDA definitions of these terms:

-“A ‘Best if used by (or before)’ date is recommended for best flavor quality. It is not a purchase or safety date.

-A ‘Use-by’ date is the last date recommended for the use of the product while at peak quality.”

So what’s the difference? Very little if any. Consumers may think that the product will last longer if the package says “best by” (which sounds discretionary) than if it says “use by” (which sounds like a command to discard). However, not all manufacturers make that distinction. To some manufacturers, “best by” and “use by” are synonymous. Therefore, don’t assume that “best by” is an invitation to keep the product another few weeks. If it’s a perishable item, be cautious. To find out how long the product should last, call the manufacturer or check online (See the next Q/A for helpful websites). Also, before eating an expired product, check it for mold, a bad smell, or other defects that might indicate contamination.

If a product says, “Expiration: 4/28/11.” There’s no ambiguity there. That’s the last date the manufacturer is advising the product’s use, either for quality or health reasons or both. Eggs are an exception. They can be used 3-5 weeks after their “sell by” or expiration date.

Source(s):

USDA Fact Sheets “Food Product Dating”

BusinessWeek “The truth About Food Expiration Dates”

ConsumerReports.org Food “The dating game”