Ketchup can go bad over time, especially in an opened bottle, but it can have a very long shelf life if you know how to store it. But you can only enjoy ketchup’s long shelf life if you know how to preserve it and how to tell when it has gone bad.
Quick Answer
Ketchup can last up to a year past its best-by date as long as it remains sealed, but once the seal is opened the ketchup will go bad after a month in the pantry or a year in the refrigerator. Ketchup, both sealed and unsealed, can easily last two years in the freezer as long as it’s in the right container.