Yes, elf bars can expire if they're not stored correctly or if they're left out in the open for too long. It's best to store them in a cool, dry place away from direct sunlight, as this will help them last longer. Additionally, you should make sure to eat them within their expiration date, which should be clearly indicated on the package. If you're not sure whether a particular elf bar has expired or not, it's always better to err on the side of caution and not eat it.