Unopened tahini lasts for up to 18 months when stored in a cool, dry place. We generally recommend using your tahini within 12 months and storing it in the fridge to maintain freshness and slow the separation of natural oil in the sesame seeds, which may start to occur after a few months. However, tahini is shelf stable out of the fridge whether it is open or unopened. If you notice that your tahini has a layer of oil at the top, that doesn’t mean it’s gone bad! All you need to do is stir the jar. You can also safely store your tahini in a cool pantry.