Yes, Disneyland is extremely crowded during the Halloween season, which in 2026 officially runs from late August through October 31st. This has become one of the most popular times of year to visit due to the unique "Halloween Time" decorations, seasonal food, and the massive popularity of the Oogie Boogie Bash, a separately ticketed event at Disney California Adventure. During this period, weekends and the weeks surrounding school fall breaks are typically at "Capacity" or "Peak" levels on crowd calendars. Popular attractions like Haunted Mansion Holiday (the Nightmare Before Christmas overlay) can see wait times exceeding 90 to 120 minutes. Even on weekdays, the parks feel very full as locals flock to see the giant Mickey pumpkin on Main Street. If you plan to visit during this time, it is essential to make park reservations months in advance and consider using Lightning Lane Multi Pass to navigate the high attendance levels. Despite the crowds, many guests find the festive atmosphere and rare character sightings worth the extra squeeze.