Adding guests to a Disney reservation in 2026 is primarily handled through the "My Disney Experience" (Florida) or "Disneyland" (California) mobile apps. You must first ensure the guest is in your "Family & Friends" list by sending them an invite via their email address or scanning their linking code. Once linked, you can add them to dining reservations or virtual queue entries. If you are trying to add a guest to a hotel room reservation, you may need to call Disney's central reservation line (e.g., 407-939-4357) if the change exceeds the room's maximum occupancy or if it's a "Room Only" booking. For theme park entry, you simply purchase an additional ticket and link it to their profile. Note that in 2026, most parks have moved away from strict park reservations for date-based tickets, making it much easier to add a last-minute friend to your party.