Yes, infant car seats and bases do expire and when you purchase them, you'll find the expiry date on the sticker attached to the infant car seat or at the bottom of the car seat base. Most car seats have an expiry period that does not exceed 6 years. After years of use, car seats and car seat bases become more dangerous and it gets weaker and may not be as safe for you to use with your baby. If you're wondering how they expire, just consider that the older a car seat is, the older the materials, and their protection does not give you a safety guarantee. This is the reason why the car seats expire.