Per USDA FoodKeeper
On the counterCounter
Refrigerate
once opened
In the fridgeFridge
3 days
at or below 40°F (4°C)
In the freezerFreezer
1 month
at 0°F; quality, not safety
On the counterCounter
Not recommended
keep it cold
In the fridgeFridge
6 months
at or below 40°F (4°C)
In the freezerFreezer
1 month
at 0°F; quality, not safety
Quick answer
Yes. Pesto lasts 3 days in the fridge and 1 month in the freezer. After that, or sooner if stored badly, it spoils: watch for the signs below.
How to tell if pesto is bad
Smell
Fermented, yeasty or sour beyond the product's usual tang.
Texture
Separation that does not stir back, or a slimy layer.
Colour
Darkening or a change in colour at the top of the jar.
Mould
Any fuzz on the surface or lid — discard the jar.
Pesto past the expiration date
Unopened
FoodKeeper gives unopened pesto 6 months in the fridge, counted from the day you buy it. "Best-by" and "sell-by" describe quality and stock rotation, not safety; only infant formula carries a federally required use-by date.
Opened
Once opened, the printed date no longer applies. Count 3 days in the fridge from the day you open it.
How to keep pesto fresh longer
- Refrigerate after opening unless the label says otherwise.
- Use a clean utensil each time; crumbs and double-dipping shorten shelf life.
- Wipe the rim and close the lid tightly.
More about pesto
FAQ
How long does it take for pesto to go bad?
3 days in the fridge, per USDA FoodKeeper.
Can pesto expire?
FoodKeeper gives unopened pesto 6 months in the fridge, counted from the day you buy it. "Best-by" and "sell-by" describe quality and stock rotation, not safety; only infant formula carries a federally required use-by date.
What happens if you eat bad pesto?
Usually an unpleasant taste rather than illness, but discard anything mouldy, rancid or smelling off.
How do you keep pesto from going bad?
Refrigerate after opening unless the label says otherwise.
Numbers on this page come from USDA FoodKeeper and FSIS guidance. Last verified November 2026. How we verify our data · Report a wrong number