Typically these tarts will have a best before date of around 3 or 4 months after the date you receive them. However, they may last several months longer than this best before date without significant quality loss. If they get a little stale, they can be toasted in the oven to refresh them.
We suggest storing at room temperature, as refrigeration may lead to them getting softer due to moisture absorption, not to mention picking up smells from other ingredients in the fridge.