Hiya, Melissa!
Yes, unless restrictions are indicated on the tickets, most standard
theme park tickets are upgradeable. A currently valid or wholly unused
one-day park ticket may be
upgraded to a higher-tier ticket or even to a multi-day ticket. To do so, you may stop by a main entrance ticket booth at the Disneyland Resort and simply pay the difference in price between what was originally paid for the ticket and the current-day price of the new ticket. Please note that you will need to make a theme park reservation with the new ticket as well. So it is a good idea to check the
theme park reservation availability calendar to make sure that there are openings to book for the day you wish to visit.
Tony’s Tip: If you want to make sure you have a
theme park reservation in place before you visit the ticket booths to upgrade your ticket, you may purchase a new ticket online ahead of time. Then, take both the old, unused ticket and the new ticket to the ticket booths. You may then request that the old ticket be canceled and refunded as an exception to the
nonrefundable policy. I recommend taking your photo ID and the original form of payment for the tickets with you as you request the ticket upgrade.
I hope you have a magical time at the Disneyland Resort, Melissa!
~Tony