Yes, hydration packs (like CamelBaks) are permitted in all Walt Disney World and Disneyland theme parks in 2026, provided they meet the standard park bag regulations. The main rule is that the bag itself must not exceed 24" long x 15" wide x 18" high. It is a peer-to-peer essential to know that while you can bring the pack, loose ice is strictly prohibited in any container at Disney; you should use reusable ice packs or fill the bladder with ice at your hotel. During the security screening, be prepared to open all pockets of the pack for inspection. Hydration packs are a high-value strategy for surviving the Florida or California heat, as they allow you to sip water constantly while waiting in long Lightning Lane queues. You can refill your bladder for free at any "Quick Service" food location or at the dedicated water bottle refill stations found near many restrooms, ensuring you stay hydrated throughout a 12-hour park day without paying the "premium" $5+ price for bottled water.