If you didn’t know it by now, you should know that ketchup expires. Fortunately, it won’t happen overnight. You can store an unopened bottle of ketchup in the pantry for at least a year. Once it’s opened, it’s shelf life noticeable decreases. If you’ll store an opened bottle of ketchup in a cool place, like in the fridge, it should be fine for at least half a year. If you use a lot of ketchup, you can keep it in the pantry, or even in room temperature – it should be fresh and tasty for at least a couple of weeks.