Governor Josh Green signed Act 259 (HB 2021) on July 15, 2026, giving Hawaii its first comprehensive statewide e-bike framework. The law requires helmets for all riders under 18, bars anyone under 15 from operating an e-bike, and prohibits riders under 16 from using Class 2 or Class 3 models without adult supervision.

The measure grew out of an alarming rise in head trauma. Hawaii Department of Health data reported that e-bike injuries more than doubled between 2022 and 2025, from 106 to 244. Honolulu EMS also found that 81 percent of the e-bike patients that were treated wore no head protection. Honolulu-based Kapi’olani Medical Center’s trauma team reported that e-bike crashes recently became the leading cause of injury among the children it treated.

Green, previously an emergency physician, has been blunt about the stakes. “If they have a head trauma, they’re probably going to have long-standing disability from the traumatic head injury,” he said in a September 2025 interview.

The law also reclassifies machines exceeding 28 mph as e-motorcycles, subject to licensing, registration, and insurance. California imposes comparable rules, while New Jersey now goes further, requiring helmets for e-bike riders of every age.

See also: E-Bikes and Brain Injury: The Risks, the Recovery, and the Law