No, you cannot make a Disney theme park reservation without a valid ticket. The Disney Park Pass system (used at both Walt Disney World and Disneyland) requires you to have a valid admission ticket or a Magic Key/Annual Pass linked to your MyDisney account before the reservation calendar becomes accessible to you. When you begin the reservation process, the system first verifies that you have "active entitlements." If you attempt to reserve a date without a linked ticket, the app or website will prompt you to purchase one or enter a ticket ID number first. It is important to note that as of 2024 and through 2026, Disney World has removed reservation requirements for date-based tickets (standard tickets where you choose a start date at purchase). However, for non-dated tickets, Annual Passes, and certain promotional fares, reservations remain mandatory. Because park capacity is limited, the recommended workflow is to check the "Availability Calendar" first, then immediately buy your ticket and secure your reservation in one session.