Under the current 2026 rules at Walt Disney World and Disneyland, you only need one theme park reservation for the first park you plan to visit. Once you have entered that first park, the "Park Hopper" benefit typically activates at 11:00 AM (Disneyland) or any time (Walt Disney World), depending on the specific seasonal policy in place. You do not need a separate reservation for the second, third, or fourth park you visit that day. However, your ability to "hop" is subject to the capacity of the destination park. If a park like Magic Kingdom reaches maximum capacity, you may be temporarily blocked from entering until other guests leave. Disney usually sends "push notifications" via their official apps to alert Park Hoppers if a specific park is "at capacity," so it's wise to check the app status before taking the monorail or bus to your next destination.