Unfortunately, there isn't an option to visit for a half or partial day. I would suggest that you consider adding another day to your existing ticket if a theme park reservation is available for the half-day you would like to visit.

Officially, Disney does not sell half-day tickets at Walt Disney World or Disneyland in 2026. A standard ticket is a "full-day" admission, regardless of whether you arrive at 8:00 AM or 4:00 PM. However, there are two unofficial "half-day" workarounds. The first is Special Event Tickets, such as "Mickey’s Not-So-Scary Halloween Party" or "After Hours" events; these allow entry as early as 4:00 PM for an event that runs until midnight, effectively serving as a half-day ticket for a lower price than a standard day pass. The second is Convention Tickets, which are sometimes available to guests attending conferences at Disney resorts and offer admission after 1:00 PM or 5:00 PM. For the general public, the most flexible option is the "Park Hopper" add-on, which allows you to spend half your day in one park and the other half in another. If you only have a few hours, a 1-day ticket is a poor value, as the "per-day" cost of Disney tickets only significantly drops when you purchase a 4-to-10-day multi-day pass.