Baked Goods

How long does packaged yeast last?

2 years
Pantry, from purchase — USDA FoodKeeper guidance for yeast (packaged)

A sealed packet of yeast keeps 2 years in a cool, dry pantry, but once it’s open USDA moves it to the cold: 4 months in the fridge or 6 months in the freezer.

How long does it keep?

Pantry, from purchase 2 years
Fridge, opened 4 months
Freezer 6 months
  • Pantry, from purchase: Store in cool, dry place. Must be refrigerated or frozen once opened.

Can you freeze yeast? YES, FREEZE IT

Can it sit out?

Unopened, packaged yeast is shelf-stable. Once opened, treat it as perishable — the FSIS 2-hour rule applies.

Perishable food left at room temperature for more than 2 hours should be thrown out — 1 hour if it’s 90°F or hotter (a picnic, a hot car, a summer kitchen).

The 2-hour rule, in full →

How to tell if packaged yeast has gone bad

  • No foam or froth when you proof a pinch in warm sugar water
  • A flat, cardboard smell instead of the yeasty tang
  • Granules clumped together from a damp scoop

When in doubt, throw it out.

Proof a pinch before you commit five cups of flour to it — dead yeast is the one pantry failure you can test for in a glass.

Quick answers

How long does packaged yeast last?

A sealed packet of yeast keeps 2 years in a cool, dry pantry, but once it’s open USDA moves it to the cold: 4 months in the fridge or 6 months in the freezer.

Can you freeze packaged yeast?

Once the packet is open, yeast belongs in the cold — USDA gives it 6 months in the freezer against 4 months in the fridge.

How long can packaged yeast sit out?

Sitting out isn’t the safety question for unopened packaged yeast — once opened, the FSIS 2-hour rule applies. Perishable food left at room temperature for more than 2 hours should be thrown out — 1 hour if it’s 90°F or hotter (a picnic, a hot car, a summer kitchen).