The federal standard: CPSC 16 CFR Part 1203
Every bicycle helmet sold in the United States must comply with the Consumer Product Safety Commission’s standard, 16 CFR Part 1203. It sets requirements for impact attenuation, retention-system strength, peripheral vision and labeling, and it applies whether the bicycle has a motor or not. There is no separate federal e-bike helmet standard. A helmet with the CPSC label meets the same test whatever it costs; the price buys fit, weight, ventilation, style and, sometimes, rotational protection. It does not buy a different crash test.
Practical consequence: the cheapest pick below, the Retrospec Silas, and the most expensive, the Thousand Chapter, both have to pass the same CPSC impact test to be sold as bicycle helmets in the U.S. That is the floor, and the floor is high.
The e-bike standard: NTA 8776
NTA 8776 is a Dutch standard introduced in 2015 for speed pedelecs, which assist to 45 km/h — about 28 mph, close to the top assisted speed of a U.S. Class 3 e-bike. Compared with a conventional bicycle helmet standard, a helmet certified to it has to absorb higher-energy impacts and cover more of the head, particularly the temples and the back of the skull, which are the areas most exposed in a faster fall. The helmets still look like bicycle helmets, not motorcycle helmets.
Two honest caveats. First, NTA 8776 is not required anywhere in the U.S., and a CPSC helmet remains the legal helmet for every class of e-bike. Second, the sources we could verify for the standard’s details are helmet makers’ own explainers, not the Dutch standards body, whose product page was not reachable when we checked; we have cited the clearest of them below and kept our description to what they agree on. None of the helmets in our registry carries NTA 8776. If you ride a Class 3 bike at 28 mph regularly, it is worth searching for one specifically, and we will add one to this page when we can verify a listing.
MIPS and rotational protection
MIPS is a low-friction layer inside the helmet that lets the shell slide a few millimeters relative to your head in an angled impact, which is intended to redirect some of the rotational force that an oblique hit would otherwise transfer to the brain. It is not a substitute for the CPSC test; it sits on top of it. Of the three picks, the Giro Register MIPS II and the Thousand Chapter have it; the Retrospec Silas does not, which is stated on its card and is the reason it is the cheapest of the three. At e-bike speeds, where most falls are angled rather than straight down, rotational protection is the upgrade we would pay for first. Our helmet roundup covers the full set of certified helmets we list.
What changes at 28 mph
The physics is not subtle. Kinetic energy rises with the square of speed, so a fall at 28 mph carries roughly twice the energy of one at 20 mph. That is the reasoning behind NTA 8776, and it is why we distinguish between the classes on this page rather than giving one answer. It is also why several states require a helmet for all Class 3 riders regardless of age; our classes and laws guide has the detail, and how fast do e-bikes go explains what each class actually feels like.
Fit is the whole game
A certified helmet that sits on the back of your head, or rocks when you shake it, does not deliver the protection it was tested for. NHTSA’s fit guidance is the two-finger rule: the front rim sits two finger-widths above your eyebrows with the helmet level and flat on the head; the side straps form a V around each ear; and with the buckle fastened you can fit just two fingers between the straps and your chin, snug but not tight. Never buy a helmet to grow into. A dial-fit retention system, which the Giro and the Retrospec state, makes the shell adjustment a matter of seconds and is worth more than any styling feature.
Lights, buckles and the reasons you keep it on
The best helmet is the one on your head every ride, which is why two of the three picks have a built-in rear light and one has a magnetic buckle you can fasten in gloves. A helmet light is a supplement to a real rear light, not a replacement; our lights roundup ranks the ones that count. And replace any helmet that has taken a hit, even one that looks fine: the foam does its job by crushing once.
The law, briefly
Helmet laws for e-bikes are set by the states. Many require a helmet for riders under a set age on any class, and for all riders on Class 3. None of them require anything beyond the CPSC standard. Check the PeopleForBikes state-by-state reference in the sources below, and treat the law as a minimum rather than a recommendation.
