Generally, Universal Studios parks allow 14-year-olds to enter the theme parks without an adult, as their general policy typically states that children aged 14 and older can act as "supervising companions" for younger children. However, there are significant exceptions to this rule depending on the specific event or time of day. For example, during special events like "Halloween Horror Nights," or at specific locations like Universal CityWalk after a certain hour, a "Chaperone Policy" may be in effect requiring guests under 16 or 21 to be accompanied by an adult. Additionally, while a 14-year-old may be allowed through the gate, they cannot check into most nearby hotels, as the minimum age for hotel registration is usually 18 or 21. Parents should also consider that a minor alone in the park may have difficulty handling medical emergencies or security issues without a legal guardian present. Always check the specific "Terms of Entry" for the date of your visit, as these policies can be updated during peak seasons or for security reasons.