Yes, you can change your Disney park days in 2026, but the process depends on reservation availability. Using the "My Disney Experience" app (for Disney World) or the Disneyland app, you can "Modify" an existing park reservation without having to cancel it first. You simply select the "Modify Reservation" button, choose the members of your party, and pick a new date or a different park from the live availability calendar. In 2026, this is much easier than in the early 2020s, but "sold out" dates still occur during peak seasons like Spring Break or the December holidays. If your ticket is a date-based multi-day ticket, you must ensure the new date falls within the "validity window" of your original purchase; if the new date is in a higher-priced tier (such as moving from a Tuesday to a Saturday), you may be required to pay the price difference before the change is finalized.