Once opened, Tuna (packet) keeps about 3–4 days in the fridge. Unopened, it keeps about 18 months.
3–4 days opened in the fridge, against 18 months sealed in the pantry. Green is what this situation leaves you; husk is what it spends.
| Situation | Keeps for |
|---|---|
| Unopened · pantry | 18 months |
| Opened · fridge | 3–4 days |
Air and warmth are what shorten an opened item's life — the right container buys back the days the packaging gives up once the seal's broken.
Keep Tuna fresh longer ↗ Need a fresh one? ↗
Ad · Affiliate links — we may earn a commission at no cost to you. They appear after your answer and never change it.
About 3–4 days refrigerated at 40°F (4°C) or below, according to USDA FoodKeeper v128. Refrigerate it once it's open.
Yes — keep Tuna (packet) at 40°F (4°C) or below once it's open. Cool, dry pantry unopened; refrigerate at 40°F (4°C) or below after opening.
Look for: A rancid, paint-like, or musty smell; Bulging, leaking, deeply dented, or rusted cans; Insects or webbing in dry goods; Mould or discoloration. Those are the general signs for pantry staples — USDA FoodKeeper v128 publishes no spoilage note for Tuna (packet) specifically. Never taste something to test it — when in doubt, throw it out.