Waxworms generally last about 2-3 weeks when they're kept in a refrigerator door, as long as the temperature doesn't dip below approximately 45°F. Removing dead waxworms from the cup is paramount to preventing a mass die-off. The better you take care of them, the fewer of them will die before you have a chance to feed them off. If you want to maximize their lifespan for long-term feeding and bulk orders, check out our tips and tricks for keeping your waxworms alive longer.