September is widely regarded as one of the best months to visit Disneyland due to the "back-to-school" drop in general attendance, but you should time your visit carefully around the popular Halloween season. In 2026, the best window for low crowds is the first two weeks of the month, specifically mid-week (Tuesday through Thursday), after the Labor Day holiday weekend has concluded. However, be aware that Halloween Time at the Disneyland Resort officially begins in late August and runs through October 31. This brings festive decor and the "Oogie Boogie Bash" after-hours event on select nights (including Sundays, Tuesdays, and Thursdays in September). On event nights, Disney California Adventure closes early to regular guests, which can push crowds over to Disneyland Park, making it feel busier. If you aren't attending the party, the "sweet spot" is a Monday or Wednesday in early-to-mid September when the weather is still warm but the "spooky" crowds haven't reached their October peak. Also, keep an eye on the schedule for the new Soarin' Across America limited-time run, which may draw local enthusiasts during this period.