How long do potato chips last, sealed and opened?
Quick answer
- In the pantry
- Unopened: until the best-if-used-by date (USDA: about 2 months from purchase) · Opened, clipped shut: 1–2 weeks
Sources: USDA FoodKeeper, USDA FSIS: Food Product Dating, University of Georgia Extension: Food Storage for Safety and Quality (FDNS-E-119), Pacific Northwest Extension PNW 612: Storing Food for Safety and Quality, Marasca et al., Food Chemistry (2016): Nitrogen flushing and lipid oxidation in potato chips, McGill University Office for Science and Society: the smell of rancid fat, Alabama Cooperative Extension System: Kitchen Blunders, NDSU Extension: Food Freezing Guide (FN403) · Last reviewed October 25, 2026
An unopened bag of potato chips keeps its best quality until the date printed on it; USDA's FoodKeeper and University of Georgia Extension put unopened chips at about 2 months in the pantry (USDA counts from the purchase date). Once the bag is open, plan to finish it within 1–2 weeks, clipped shut between snacks. On chips the date often reads "best if used by," which marks peak flavor and quality, not a safety cutoff. Past it, quality fades gradually: chips lose crispness, and their frying oil slowly reacts with oxygen and turns rancid, which researchers name as the main reason chips deteriorate. With an older bag, trust your nose over the calendar.
How to store chips
Two things wear chips down: moisture from the air, which takes away their crunch, and oxygen, which slowly turns the frying oil rancid. Heat and light speed that oxidation up, so keep bags in a cool, dark cupboard, not above the stove or next to the fridge's warm exhaust. Extension guides recommend pantry temperatures below 29°C (85°F), ideally 10–21°C (50–70°F), and a tight seal, since dry snacks left open soak up moisture, especially when humidity tops 60%. Many sealed bags are flushed with nitrogen instead of air, which slowed oil oxidation in a University of Nottingham study of potato chips. Opening the bag lets ordinary air in, so close it tightly every time.
- Open the bag neatly across the top so you can roll it down and close it tightly again.
- Before closing, press out the air, roll the top down several times and clip it; if the bag is torn, tip the chips into an airtight container.
- Pour a serving into a bowl and close the bag right away instead of leaving it open on the couch or the party table.
- Store bags in a cool, dark cupboard away from the oven, stove, hot pipes and the fridge's exhaust, ideally at 10–21°C (50–70°F).
- Write the opening date on the bag and finish it within 1–2 weeks; when you have several bags, open the one with the earliest date first.
Signs it has gone bad
- An unpleasant smell like cooking oil that has sat in the cupboard for months: the fat has gone rancid, so throw the chips out.
- An off flavor, even if the chips look and crunch normally: stop eating and toss the bag.
- Soft, chewy or bendy chips are stale, not rancid: they have soaked up moisture from the air. If they smell fine, you can crisp them up again.
- Chips that got wet, stuck together in clumps or show any mold: throw out the whole bag.
Frequently asked questions
Can you eat chips after the best-by date?
Often, yes: on chips the "best if used by" date is about flavor and quality, not safety. Past it, smell the chips before eating; soft ones can be crisped up, but an old-oil smell or off flavor means they are rancid. When in doubt, throw them out.
How long do chips last once opened?
About 1–2 weeks in the pantry if you roll the bag down tightly and clip it, or move the chips to an airtight container. Left open, they go soft much sooner, especially in a humid kitchen.
What's the difference between stale and rancid chips?
Stale chips have absorbed moisture and lost their crunch. Rancid chips have frying oil that has reacted with oxygen, which gives them an unpleasant old-oil smell and taste. Stale chips can be crisped up again; rancid ones belong in the trash.
How do you make stale chips crispy again?
Spread them on a baking sheet and put them under the broiler for a few minutes, watching closely so they don't brown. This only fixes texture: heat won't rescue chips that smell rancid.
Can you freeze potato chips?
Yes, though it's rarely needed. NDSU Extension's freezing guide notes that chips stay crisp when packaged tightly and frozen, which can help with a bulk buy you won't finish soon.