Universal helmet laws — state laws that require helmet use for all riders (operators and passengers) — are extremely effective.
In 2023, 94% of motorcyclists observed in states with universal helmet laws were wearing helmets. In states without such laws, helmet use was 72% (NHTSA, 2024). Use of helmets judged to be compliant with federal safety regulations was 83% among motorcyclists in states with universal helmet laws and 66% in states without such laws.
Helmet laws that apply only to young riders are virtually impossible to enforce.
Decades ago, the federal government required states to pass universal helmet laws in order to be eligible for certain safety and highway construction funds. As a result, all but three states had such laws in 1975. Once this incentive was removed in 1976, states began to repeal or weaken their laws.
Today, only 17 states and the District of Columbia have universal helmet laws, and 30 states have laws covering some riders, usually people younger than 18. Three states (Illinois, Iowa and New Hampshire) do not have any helmet requirements.
Motorcycle helmet use laws by state in detail
Over 22,000 motorcyclists are estimated to have died in crashes during 1976-2022 as a result of lower helmet use in states without universal helmet laws (Teoh, 2024). This represents 11 percent of all motorcyclist fatalities during these years.
By state, the largest number of lives lost – 2,536 – was in California, primarily due to its large population and long riding season. However, California has required all riders to wear helmets since 1992, so this number stopped growing at that time. Other states with high numbers of deaths due to lax helmet laws include Texas (2,490), Florida (1,786), Illinois (1,738), Ohio (1,651), Indiana (1,151), and South Carolina (1,000). Those states still allow unhelmeted riding, so their toll will continue to rise.
Various states have enacted and repealed universal helmet laws between 1976 and today. When states enact such laws, deaths, injuries and medical costs go down. When they repeal them, the reverse usually happens.
- When California’s helmet use law covering all riders took effect in 1992, the number of motorcyclist fatalities decreased 37% (Kraus et al., 1994).
- Nebraska reinstated a helmet law in 1989, after repealing an earlier law in 1977. The state then saw a 22% reduction in serious head injuries among motorcyclists (Muelleman et al.,1992). Acute medical hospital charges for injured motorcyclists declined 38%. Despite these benefits, Nebraska has weakened its helmet law to exempt riders 21 and older who submit proof of completing a rider training course. This takes effect Jan. 1, 2024.
- From 1968 to 1977, Texas had a universal helmet use law estimated to have saved 650 lives, but the law was amended in 1977 to apply only to riders younger than 18. The weakened law coincided with a 35% increase in motorcyclist fatalities. Texas reinstated its helmet law for all motorcyclists in 1989. Serious injury crashes per registered motorcycle decreased 11% (Mounce et al., 1992). But in 1997, Texas again weakened its helmet law, requiring helmets only for riders younger than 21. Operator fatalities increased 31% in the first full year following the repeal (Preusser et al., 2000).
- Kentucky repealed its universal helmet law in 1998, followed by Louisiana in 1999. Motorcyclist deaths quickly increased in these states by 50% and 100%, respectively (Ulmer & Preusser, 2003).
- In 2000, Florida’s universal helmet law was weakened to exempt riders 21 and older who have at least $10,000 of medical insurance coverage. An Institute study found that the motorcyclist death rate in Florida increased by about 25% after the state weakened its helmet law (Kyrychenko & McCartt, 2006). Hospital admissions of motorcyclists with head injuries increased 82% during the 30 months following the law change (Ulmer & Northrop, 2005). The average inflation-adjusted cost of treating these injuries went up from about $34,500 before the helmet law was weakened to nearly $40,000 after — 4 times the $10,000 minimum medical insurance requirement.
- Michigan weakened its universal helmet law in 2012 to exempt riders 21 and older who have at least $20,000 of medical insurance coverage and have either passed a motorcycle safety course or held a motorcycle license endorsement for at least two years. The change was associated with a 22% increase in the average insurance payment for injuries to motorcyclists (HLDI, 2013), as well as increased head injuries and neurological interventions, but no significant change in deaths (Carter et al., 2017).