Howdy Anthony!
A very warm welcome to planDisney! We’re delighted you brought a question our way!
I am so pleased that you are aware of the requirement for making an advanced
Theme Park Reservation as this reservation is required in addition to your valid admission ticket. But, to upgrade your One Park Per Day Theme Park
ticket to include the Park Hopper Option, you will have to make this change in person at the Disneyland Resort Main Entrance Ticket Booth or at
Guest Relations. Please note this upgrade is subject to availability. I recommend checking the
Availability Calendar to see if there is a Park Hopper Option available on your desired date. If you are able to upgrade, you will start at the theme park you originally chose and be able to hop to the other theme park at 1:00 p.m. You are not required to make an additional theme park reservation to visit the second park or hop back and forth between both parks. But, as always, theme park admission is subject to attendance availability.
If you have more questions, send them our way!
Tiffanie