There are a number of different dates that may appear on a product. “Open Dating” is the use of a calendar date (rather than a code) on a product. “Closed Dating” is the opposite and refers to the use of a code or packing number (rather than a calendar date) on a product. If Open Dating is used, the date must include the day and month. The year must also be included for shelf stable or frozen products. When dates are used, there must also be an explanation of the date, such as Sell-By or Use-By, etc. Federal regulations do not require product dating, except for infant formula and FDA inspected baby food. However, not all baby food is FDA inspected.

Unfortunately, there isn’t a universal system for dating food products in the United States. While food dating is required in 20 states, other parts of the country do not have such requirements. When used, open dating is normally seen on perishable foods such as meat, poultry, eggs and dairy products. Closed dating may be used on shelf-stable products, including canned and boxed foods.

For Open Dating, there are a number of formats that may be used as follows:

Sell-By – tells the store how long the product can be displayed.

Best if Used By (Best if Used Before) – for best quality or flavor, the product should be used before this date. The product is generally safe to use for days after this date. However, its nutritional value maybe compromised somewhat.

Use-By – the last date for use of the product at peak quality.

All dates are determined by the manufacturer. Closed Dating or Coded Dating is the use of a packing number on the product. This is used by the manufacturer and is not normally easily decipherable by the consumer. In case of a recall, the manufacturer can inform the public not to use the product in question, with such a number.

Foods can remain safe and of good quality after the date expires, if they have been handled and stored properly. However, they may also be unsafe or of poor quality before the date expires, if they have not been handled or stored properly to begin with. Perishable foods should normally be stored at 40°F or below. Mishandling of foods may involve leaving refrigerated foods outside for hours, defrosting at room temperature for long hours or not using sanitary handling practices.

For infant formula and FDA inspected baby food, a Use-By date is required. The product is required to contain the stated quantity of nutrients listed on the label by that date. The manufacturer determines the Use-By date based on analysis throughout the shelf life of the product or other methods. Consumers should not use baby food or formula after the Use-By date.

For canned goods, a packing code is required. This is used to track products during commerce or if there is a recall, and to allow producers to rotate their stock. The packing code is not intended for consumer use. When purchasing canned products, make sure the cans are in good condition.

The US Department of Agriculture Food Safety and Inspection Service offers the following tips on storage and usage times for food products:

  • Always purchase before the expiry date.
  • Refrigerate perishable foods promptly. Freeze within the time guidelines presented below, if you do not plan to use the product during these time limits.
  • Follow handling recommendations listed on the product.

If not used immediately, the following products should be refrigerated at 40°F or below. If the product has a Use-By date, it should be used by that date. If it has a Sell-By date or no date, it should be cooked or frozen within the following time:

Poultry 1-2 days
Beef, Veal, Lamb 3-5 days
Ground meat, Ground Poultry 1-2 days
Uncooked beef or Turkey Sausage 1-2 days
Eggs 3-5 weeks
For processed products that were packed at the plant, the following times apply when stored below 40 degree F UNOPENED AFTER PURCHASE AFTER OPENING
Cooked Poultry 3-4 days 3-4 days
Vaccuum packed dinners (commercial brand with USDA seal) 2 weeks 3-4 days
Hot dogs 2 weeks 1 week
Luncheon Meat 2 weeks 3-5 days
Canned meat and poultry, Shelf Stable 2-5 years at room temperature 3-4 days

Again, if the product has a foul odor, flavor or appearance, don’t use it. More information is available at the FSIS web site at or by calling them at 1-888-MPHotline.