Yes, you are absolutely allowed to bring water bladders (such as CamelBaks) or hydration packs into Disney World and Disneyland in 2026. This is a high-value strategy for staying hydrated in the intense Florida or California heat without constantly purchasing expensive bottled water. The only restriction is that the pack must adhere to the standard bag size limits: it cannot exceed 24" long x 15" wide x 18" high. You are permitted to bring the bladder into the park either empty or pre-filled with water and ice. For 2026, Disney has expanded its network of bottle-filling stations and "hydration hubs" throughout the parks, making it easy to refill your bladder for free. A helpful peer tip is to use the "Food & Beverage" map in the My Disney Experience app to locate the nearest filtered water station. Just be prepared to remove the bladder from your bag at the security scanners if requested, though modern Evolv scanners often allow you to walk through with the pack still on your back.