A kids’ bike helmet has to match the activity, fit the child’s head today and be adjusted every time it goes on. This guide brings together the CPSC’s guidance on which helmet to use, NHTSA’s step-by-step fitting instructions, and the Bicycle Helmet Safety Institute’s advice on choosing and replacing helmets.
Why a properly fitted kids’ bike helmet matters
According to the Consumer Product Safety Commission (CPSC), wearing a helmet can reduce the risk of a severe head injury and even save your life during a fall or collision. The CPSC explains that a helmet absorbs much of the impact energy that would otherwise reach your head and brain. No helmet design has been proven to prevent concussions, and the CPSC warns against claims that a particular helmet can reduce or prevent them. The protection a helmet provides depends on achieving a proper fit and wearing it correctly. For bicycle helmets, the chin strap is essential: the CPSC bicycle standard requires that chin straps be strong enough to keep the helmet on the head and in the proper position during a crash.
The Bicycle Helmet Safety Institute (BHSI) notes that head injuries cause 75% of the nearly 700 annual bicycle deaths in the U.S. Medical research shows that bike helmets reduce or prevent most of cyclists’ head injuries. The average careful bike rider may still crash about every 4,500 miles, and even a low-speed fall on a bike path can cause a serious head injury. For kids, the stakes are even higher. The National Highway Traffic Safety Administration (NHTSA) points out that more children ages 5 to 14 go to emergency rooms for bicycle-related injuries than for any other sport, and many of those are head injuries.
Which helmet for which activity
The CPSC is clear: there are different helmets for different activities, and each type is made to protect your head from the impacts typical of that sport. A helmet designed for one activity may not protect your head as effectively during another. For bicycling, recreational in-line skating, roller skating, and riding a kick scooter, you can wear a CPSC-compliant bicycle helmet. The CPSC’s helmet table also lists BMX cycling, downhill mountain bike racing, and longboarding as activities that require their own specific helmet types and standards.
BHSI adds that extreme, trick, and aggressive skating or skateboard helmets should meet ASTM F1492, a standard that uses multiple hits and lesser impact severity. Those helmets may not handle bicycling impacts. BHSI warns: do not use a skate helmet for bicycling unless it has a CPSC sticker inside. The best skate helmets are dual-certified to both F1492 and the CPSC bicycle helmet standard.
If your child rides a powered scooter or motorized bicycle capable of maintained speeds of at least 20 mph, the CPSC says a moped or motorcycle helmet may be appropriate because of the greater interaction with motor vehicles. For slower motorized riding that resembles bicycle use, a bicycle helmet may still be suitable. Always check the activity table in the CPSC’s “Which Helmet for Which Activity” brochure and look for the applicable standard label inside the helmet.
How to find the right size
NHTSA’s fitting guide starts with measuring the child’s head to find a size. Helmets come in various sizes, just like hats, and size can vary between manufacturers. NHTSA recommends trying on several helmets in the measured size until one feels right. Once the helmet is on, adjust the sizing pads or fit ring until it is snug. BHSI emphasizes that a good fit means the helmet is level on the head, touching all around, and comfortably snug but not tight. The helmet should not move more than about an inch in any direction.
BHSI also advises buying a helmet that fits now, not a helmet to “grow into.” NHTSA says the same: buy and fit the helmet for now. If you buy a helmet the child finds comfortable and attractive, they are more likely to wear it every ride. For the youngest riders, the CPSC helmet table lists ASTM F1447 and F1898 under bicycling and notes that one of these standards is designed for infants and toddlers in activities involving non-motorized wheeled vehicles.
Step-by-step fit and strap adjustment
Follow NHTSA’s fitting steps in order.
Position the helmet level and low
NHTSA says the helmet should sit level on the head and low on the forehead, one or two finger-widths above the eyebrow. The CPSC echoes this: wear it low on the forehead, about two finger widths above the eyebrows, and sit it evenly between the ears and flat on the head. BHSI adds that covering as much of the forehead as possible is critical, and that the helmet must stay on the head even during multiple impacts, such as hitting a car first and then the road.
Side straps: form the V
Adjust the slider on both side straps to form a “V” shape under, and slightly in front of, the ears. NHTSA recommends locking the slider if the helmet has that feature. Both side straps need to be snug.
Buckles and chin strap
Center the left buckle under the chin. NHTSA notes that on most helmets, the straps can be pulled from the back of the helmet to lengthen or shorten the chin straps, and this task is easier with the helmet off. Buckle the chin strap and tighten it until it is snug. No more than one or two fingers should fit under the strap.
The yawn check and rock check
NHTSA’s final fitting check: the child should open their mouth wide, like a big yawn. The helmet should pull down on the head. If it does not, go back and tighten the chin strap. Next, check if the helmet rocks back more than two fingers above the eyebrows. If it does, unbuckle, shorten the front strap by moving the slider forward, then buckle and retighten the chin strap and check again. If the helmet rocks forward into the eyes, unbuckle and tighten the back strap by moving the slider back toward the ear, then buckle, retighten, and check again. BHSI puts it bluntly: with the strap fastened, you should not be able to get the helmet off the head by any combination of pulling or twisting. If it comes off or slips enough to leave large areas of the head unprotected, adjust the straps again or try another helmet.
Secure the rubber band
NHTSA instructs that all four straps must go through the rubber band and be close to the buckle to prevent the buckle from slipping. Roll the rubber band down to the buckle after adjustments are complete.
Fit checklist: what to look for
| Fit point | What to check | Source |
|---|---|---|
| Forehead position | One or two finger-widths above the eyebrow; level on the head | NHTSA, CPSC |
| Side straps | Form a V under and slightly in front of the ears; snug | NHTSA |
| Chin strap | Snug with no more than one or two fingers under the strap | NHTSA |
| Yawn check | Helmet pulls down on the head when mouth opens wide | NHTSA |
| Rock check | Helmet does not rock forward, backward, or side to side more than an inch | NHTSA, BHSI |
| Strap security | All four straps through the rubber band near the buckle | NHTSA |
| Overall movement | Helmet does not pull off with any combination of pulling or twisting | BHSI |
What to look for on the helmet itself
Bicycle helmets sold in the U.S. must meet the CPSC bicycle helmet standard, and NHTSA says to look for the certification label inside the helmet. BHSI agrees: look first for a CPSC sticker inside. BHSI also notes that ASTM’s F1447 standard is better, and Snell’s B-95 was tougher but is seldom used. Fit is not certified by any standard, so you must check that on the child’s own head.
BHSI recommends picking a white or bright color for visibility. Common sense, BHSI says, tells you to avoid a helmet with snag points sticking out, a squared-off shell, inadequate vents, excessive vents, an extreme “aero” shape, dark colors, thin straps, complicated adjustments, or a rigid visor that could snag or shatter in a fall. The CPSC warns against helmets that contain nonessential elements that protrude from the helmet, such as horns or mohawks: these may prevent the helmet’s smooth surface from sliding after a fall, which could lead to injury. The CPSC also says not to add stickers, coverings, or other attachments that were not provided with the helmet, as they can negatively affect performance.
When to replace a kids’ bike helmet
The CPSC states that bicycle helmets are designed to protect against the impact from a single fall. The foam material in the helmet crushes to absorb the impact energy, and it will not protect again from an additional impact. Even if there are no visible signs of damage, you must replace the helmet after such an event. BHSI confirms: replace any helmet if you crash. Impact crushes some of the foam, although the damage may not be visible. Helmets work so well that you need to examine them for marks or dents to know if you hit. The CPSC adds that dropping the helmet hard enough to cause damage also means replacement is needed. Cracks in the shell, worn straps, and missing pads or other parts are all reasons to replace a helmet.
On aging, BHSI reports that most manufacturers recommend replacement after five years, but research has shown that unless crashed, helmets perform well much longer than that. BHSI cites a 2015 MEA Forensic study that ran crash trials on 675 used but uncrashed helmets, some as old as 26 years, and found no significant impact performance change with age. Core samples from 63 helmets confirmed that helmet liner foam does not deteriorate with age. BHSI says that sweat does not degrade EPS foam, and UV inhibitors in the plastic shell control sun damage. If the shell is fading or showing small cracks around the vents, the UV inhibitors may be failing and replacement is probably wise.
For more detail on replacement timing and inspecting a helmet after a fall, see our guide on when to replace a bike helmet.
Important safety warnings for children
The CPSC and BHSI both issue a specific warning: children must not wear a helmet when playing on playgrounds or climbing trees. The CPSC explains that the chin strap can get caught on equipment or tree branches and pose a risk of strangulation. The helmet may also prevent a child’s head from moving through an opening that the body can fit through, entrapping the child by the head. BHSI provides additional information on this playground hazard.
Helmet laws vary. NHTSA notes that many states and local jurisdictions have child bicycle helmet laws, and BHSI states that laws in 22 states and at least 201 localities require helmets, although few cover adults. Check your state and city regulations. Bike laws covering lights, helmets, and e-bike classes differ from place to place, so confirm local requirements before your child rides.
Getting the right helmet for your child’s riding
For everyday riding, a CPSC-certified bicycle helmet is the correct choice. If your child also skates at a skatepark or rides a BMX track, check the CPSC activity table for the specific helmet type and standard. BHSI recommends visiting a bike shop where staff can help with fitting, because fit is important for safety. A discount-store helmet can be equally protective if you take the time to fit it carefully. BHSI also notes that rear stabilizers do not substitute for careful strap adjustment: the straps hold the helmet on, not the rear stabilizer.
Once you have the helmet, make fitting a regular habit. NHTSA says to readjust as necessary to ensure the helmet fits properly each ride. A helmet that rocked forward on yesterday’s ride may need a quick back-strap tweak before today’s.
For more on helmet types and certification labels, read our how to choose a bike helmet guide. If your child commutes to school or rides in traffic, our commuter bike helmet guide covers visibility, lights, and comfort features. Riders who hit trails should see the mountain bike helmet guide. For the full range of protective gear, visit our helmets category page and the broader cycling gear section.
Frequently asked questions
Can my child use the same helmet for biking and skateboarding?
Only if the helmet is dual-certified. The CPSC says a CPSC-compliant bicycle helmet can be worn for bicycling, recreational in-line skating, roller skating, and riding a kick scooter. BHSI warns that extreme, trick, and aggressive skating or skateboard helmets should meet ASTM F1492. Do not use a skate helmet for bicycling unless it has a CPSC sticker inside. The best option is a helmet dual-certified to both F1492 and the CPSC bicycle helmet standard.
How do I know if the helmet still fits after several months?
Repeat NHTSA’s fit checks. Make sure the helmet is still one or two finger-widths above the eyebrow, the side straps still form a V under the ears, and the chin strap is snug with no more than one or two fingers of space. Do the yawn check: the helmet should pull down on the head. Check for rocking forward, backward, or side to side. If the fit has changed, readjust the pads, fit ring, and straps. If it cannot be adjusted to fit correctly, BHSI says replace it.
Does a more expensive helmet protect better?
BHSI states that its limited checks have shown that most helmets have about the same impact protection regardless of price. An inexpensive discount-store helmet can be equally protective if you take the time to fit it carefully. The key differences are in fit systems, ventilation, weight, and shell shape. BHSI recommends looking for a smooth, well-rounded shell with a bright color and a CPSC sticker inside, then focusing on fit above all else.
Ready to explore more gear? Browse our helmets category for additional guides on choosing, fitting, and maintaining bike helmets for every rider.
