Yes, Disneyland tickets and park reservations can and do sell out, particularly during peak seasons, holidays, and special events. In 2026, with the ongoing 70th Anniversary celebration and new debuts like Bluey & Bingo, demand remains exceptionally high. Disney uses a reservation system that requires both a valid ticket and a date-specific reservation. On popular days like Christmas, Spring Break, or the opening of new attractions, the reservation calendar can fill up weeks or even months in advance. Even "1-Day Passports" have variable pricing tiers, and the cheapest tiers often sell out first. It is highly recommended to check the theme park reservation availability calendar on the official website before purchasing your tickets to ensure your desired dates are still open. If a date is sold out, it is worth checking back occasionally as cancellations may sometimes result in a small number of reservations being released back into the system.