Expiration date

An expiration date or expiry date is a previously determined date after which something should no longer be used, either by operation of law or by exceeding the anticipated shelf life for perishable goods. Expiration dates are applied to selected food products and to some other manufactured products like infant car seats where the age of the product may impact its safe use.

Arbitrary expiration dates are also commonly applied by companies to product coupons, promotional offers and credit cards. In these contexts, the expiration date is chosen for business reasons or to provide some security function rather than any product safety concern.

Expiration date is often abbreviated EXP. The legal definition and usage of the term expiration date will vary between countries and products.

An expiration date on food differs from a best-before date. According to the Canadian Food Inspection Agency "Expiration dates are required only on certain foods that have strict compositional and nutritional specifications which might not be met after the expiration date."

In Canada expiration dates must be used on the following food items (list and comments copied from CFIA website):

The concern is that after the expiration date has passed, the food may not have the same nutrient content as specified on the packaging and for the listed regulated products, the nutritional content is quite important. The CFIA recommends that food should be discarded and should not be bought, sold or eaten beyond the stated expiration date. This contrasts with a best before date which is an indication of how long properly stored prepackaged food is expected to retain its "freshness, taste, nutritional value, or any other qualities claimed by the manufacturer." Passing a best before date is not necessarily a reason to discard the food. "Sell by" and "manufactured on" dates are related concepts that may guide the consumer.

Non-food items may also carry an expiration date. For example, in Canada, all children are required to be secured in an infant car seat while in a motor vehicle that is in motion. Users are required by law to follow manufacturer's directions. There is no specific law that requires an expiration date, but all Transport Canada approved car seats sold in Canada carry a manufacturer applied expiration date that ranges between 6 and 9 years from date of manufacture. The rational is that car seats are subjected to heat, cold, sun exposure, abuse by the children, and long term storage between children, all of which can degrade the structure and function of the car seat and cause a failure during a crash event. Further, beyond the expiration date the manufacturer will no longer be monitoring the safety of the seat through testing. Transport Canada advises to destroy an expired car seat and dispose of it at a landfill or recycling facility. Never give an expired seat to someone else or to charity.

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Wikipedia