No costumes, costume masks or face paint. Outside food & drinks are not permitted in the Theme Park. Food, drinks, bottles, recording/flash photography, flashlights or laser pens are not permitted in the Mazes.

For the 2025–2026 season, Universal Studios Hollywood Halloween Horror Nights (HHN) operates under strict guidelines to ensure safety and atmosphere. Most importantly, no costumes or masks are allowed for guests to prevent confusion with the professional scare actors. The event is "rain or shine," and tickets are separately ticketed, meaning a standard daytime pass does not grant evening entry. Guests are prohibited from touching the scare actors or the elaborate props within the haunted houses; doing so can result in immediate expulsion without a refund. Additionally, while photography is allowed in the "Scare Zones," no flash photography or video recording is permitted inside the haunted houses to protect the actors' vision and maintain the element of surprise for others. Re-entry is generally not allowed once you exit the turnstiles, and the event is recommended for ages 13 and up due to its intense, mature themes.