Frito-Lay marks their products with a "freshness date". This is the date that the products may stay fresh while unopened. This applies to both chips and dip.
The freshness date on a glass jar of dip is printed on the top rim just below the lid. The dip is considered safe to eat for about 10 to 14 days after the container is opened. Frito-Lay recommends refrigerating the dip to maintain its freshness and flavor.
The freshness date for chips is printed on the front of the chip bag. Frito-Lay recommends tightly resealing opened bags and consuming snacks within 10 days of opening.