Yes, you can bring a CamelBak (hydration bladder) on a plane in 2026, but it must be completely empty when you pass through the security checkpoint. Once you are in the "Post-Security" area, you can fill the bladder at a water fountain or "hydration station" before boarding. Because CamelBaks can hold significantly more than 3.4 ounces (100ml) of liquid, a full bladder will be confiscated or required to be emptied by security officers. For long-haul flights, CamelBaks are a "pro-traveler" favorite as they allow for hands-free hydration without the need for multiple plastic bottles. Just ensure the drinking tube is tucked away during boarding and deplaning to prevent it from snagging on seats or other passengers' luggage in the crowded aisle.