Only situations with a published figure are listed. A blank isn't “forever” — it means no reliable number is published for it.
Storage
Store at: Pantry unopened; refrigerate after opening for best quality
Refrigerate after opening: Yes — refrigerate at 40°F (4°C) or below
Tip: Acidic and stable — safe at room temperature for a while once opened, but refrigeration keeps colour and flavour best. USDA FoodKeeper: 1 year pantry unopened, 6 months refrigerated after opening.
USDA FoodKeeper tip (pantry storage): Refrigeration ensures that commercial sauces and condiments stay fresh for a longer period of time.
USDA FoodKeeper tip (pantry storage): Shelf-stable commercial ketchup, cocktail sauce, and chili sauce are safe when stored at room temperature after opening.
USDA FoodKeeper tip (pantry storage): Quality, not safety, is the reason the labels on these products suggest that they be refrigerated after opening.
How to tell if Ketchup has gone bad
Darkening or browning
Off or fermented smell
Watery separation
Mold around the cap
USDA FoodKeeper publishes no spoilage note for Ketchup specifically, so these are the general signs for condiments & sauces — never taste something to test it. When in doubt, throw it out.
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.
About 6 months refrigerated at 40°F (4°C) or below, according to USDA FoodKeeper. Refrigerate it once it's open.
Does Ketchup need to be refrigerated after opening?
Yes — keep Ketchup at 40°F (4°C) or below once it's open. Pantry unopened; refrigerate after opening for best quality.
How can you tell if Ketchup is bad?
Look for: Darkening or browning; Off or fermented smell; Watery separation; Mold around the cap. Those are the general signs for condiments & sauces — USDA FoodKeeper publishes no spoilage note for Ketchup specifically. Never taste something to test it — when in doubt, throw it out.