Items marked with expiration dates consisting of only a month and year expire on what day?

Items marked with expiration dates that consist of only a month and a year are understood to expire on the last day of the specified month. This convention helps ensure that consumers utilize the product up until the end of the month, allowing for maximum usage of that item before it is no longer deemed safe or effective.

For example, if a product has an expiration date of "October 2023," it is interpreted as the product being good through the entire month of October, but it is not advised for use after October 31st. This approach avoids confusion regarding the exact moment the item is considered expired and aligns with standard practices in labeling and consumer goods management.