Who knew? Cracking the egg carton code

March 3, 2008


About one-third of the nation’s table eggs are packed under USDA’s voluntary grading service.  This service provides consumers qualified third-party assurance that the eggs they buy are the grade marked on the carton at the time the eggs are packed and that the plant processing equipment, facilities, sanitation, and operating procedures are continuously monitored by a USDA grader.  This assurance is available at little or no additional cost to consumers — eggs graded by USDA (eggs identified with the USDA grade shield) cost essentially the same as eggs without the USDA grade shield.

Only eggs graded by USDA may be packed into cartons that bear the shield-shaped USDA grademark shown here.  USDA graders constantly monitor quality, size, and packaging of these eggs.


When the USDA grade shield is present on the carton, the carton must also be labeled with the date and location of where the eggs were packed.  Consumers can also use this information to learn more about the eggs they are buying.   This information is typically stamped onto one end of each carton of eggs.  An example of a date and location code is shown in the picture below:

Cartons that have the USDA grade shield are marked to identify the company and location where the eggs were packed, and the date that the eggs were washed, graded, and placed into the cartons. In addition, most packers also provide consumers with a code date, which indicates the last date the eggs should be sold at retail, or used by the consumer.

Egg processors typically print dates commonly called “Code Dates” on cartons for purposes of rotating stock or controlling inventory.  “EXP”, “Sell By”, “Best if Used Before” are examples of terminology used for code dating.  Use of code dates on USDA graded eggs is optional, however, if they are used, certain rules must be followed.

If an expiration date is used, it must be printed in month/day format and preceded by the appropriate prefix.  “EXP”, “Sell By”, “Not to be sold after the date at the end of the carton” are examples of expiration dates.  Expiration dates can be no more than 30 days from the day the eggs were packed into the carton.

Another type of code dating used indicates the recommended maximum length of time that the consumer can expect eggs to maintain their quality when stored under ideal conditions. Terminology such as “Use by”, Use before”, “Best before” indicates a period that the eggs should be consumed before overall quality diminishes.  Code dating using these terms may not exceed 45 days including the day the eggs were packed into the carton.

The expiration date in this example is “Aug 29”.

USDA assigns a plant number to each official plant where eggs are packed under USDA’s grading service.  This number is always preceded by the letter “P” and must be stamped or pre-printed on each carton.  The plant number in this example is “P1380.”

You can find out where the USDA graded eggs you buy are packed.  Visit our List of Plants Operating Under USDA Poultry & Egg Grading Programs and follow directions to find out which plant packed your eggs.

The day of the year that the eggs are processed and placed into the carton must also be shown on each carton with the USDA grade shield.  The number is a three-digit code that represents the consecutive day of the year.  For example, January 1 is shown as “001” and December 31 as “365.”  Typically, eggs are packed within 1 to 7 days of being laid.  The pack date in this example is “218”, meaning that the eggs were packed on the 218th day of the year, or in this example, August 5. 

If your carton shows a USDA grade shield, you can determine the date that the eggs were packed from the carton date code.


Eggs that are not packed under USDA’s grading program must be labeled and coded in accordance with egg laws in the State where they are packed and/or sold.  Most States require the use of a pack date as described above.  For more information about State egg laws, contact your local State Department of Agriculture.

Source: http://www.ams.usda.gov/poultry/consumer/labelingexplained.htm

One Response to “Who knew? Cracking the egg carton code”

  1. Linda Moorcock Says:

    Eggland eggs are nasty & I’ve never eaten them. Driving up TX Hwy 79 one can see all the horrible Sanderson’s intensive chicken farms [if you can spot the small hidden signs]. Awful closed dark buildings breeding sick chickens. I don’t eat either the chickens or the eggs. I get eggs locally from friends or farmers who raise free range chickens. One only has to note the difference between an Eggland egg [pale watery yolk] and a fresh free range egg [firm bright yellow yolk] to know which is superior. No one should be forced to eat that crap.

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