How to Check and Adjust Your Child's Helmet Fit at Home

Quick answer

Do a five-minute helmet fit check before every ride: set the helmet level and low on the forehead, tighten the dial until the shell moves the scalp rather than the head, then adjust the straps so they form a V just under each ear. The helmet should not slide when your child shakes their head, and the front edge should sit about two fingers above the eyebrows.

A helmet only protects the part of the head it actually covers, and most helmets we see on the school run sit too far back, too loose, or both. You do not need a shop visit to fix that. A child helmet fit check takes about five minutes at home with no tools beyond your hands.

This guide walks through the order that works: position first, then tightness, then straps, then a real-world test. Each step includes the mistake that most often undoes it. If your child wears a Banwood ECO Helmet, the same sequence applies; the recycled ABS shell and EPS foam liner are certified to EN 1078 and CPSC standards, but certification assumes the helmet is worn correctly.

Before you start: what you need and when to recheck

You need the helmet, your child, and a mirror or phone camera so they can see what you are doing. Do the check indoors, standing still, before anyone is in a hurry. A helmet that was perfect in spring can be loose by autumn because kids grow, hair gets thicker or thinner with the seasons, and straps stretch with use.

Recheck the fit after a growth spurt, after a haircut, whenever the helmet has been dropped or stored in a hot car, and any time you change the padding or add a hat underneath. If your child wears a Banwood ECO Helmet in ivory or lavender, the 50-54 cm size range covers a wide span of ages, so the dial and straps do most of the work of keeping it stable.

• Check the fit with the same hairstyle your child will ride with.
• Do not add thick hats under a helmet unless the helmet still sits level and low.

Step 1: Position the helmet level and low

Place the helmet on your child's head with the front edge about two fingers above the eyebrows. It should sit level, not tilted back like a sun visor or tipped forward over the eyes. This is the single most common mistake: a helmet pushed back leaves the forehead exposed, which is exactly where a front-impact fall lands.

If the helmet naturally rides up, the problem is usually tightness or strap length rather than the helmet itself. Fix the position now, because tightening a badly placed helmet just locks in the wrong coverage.

• Checkpoint: the front rim should be visible in your child's upward gaze.
• If the helmet only stays level when the chin strap is very tight, the size or shape may be wrong.

Step 2: Tighten the fit dial until the scalp moves

Turn the rear dial until the helmet feels snug all the way around, with even pressure and no pressure points. The test: with the chin strap undone, have your child open their mouth wide or raise their eyebrows. The helmet should pull down slightly and move the scalp with it. If the helmet stays still while the head moves inside it, it is too loose.

Snug is not the same as painful. You should be able to slide one finger under the rim at the front, and your child should be able to talk and swallow normally. If they complain about pressure above the ears or at the forehead, loosen the dial one click and recheck.

• Mistake to avoid: overtightening the dial to compensate for straps that are too long.
• A helmet that leaves red marks after ten minutes is too tight, not too safe.

Step 3: Adjust the straps into a V under each ear

Adjusting helmet straps comes down to two things: the side straps should meet in a V just below each earlobe, and the chin strap should be tight enough that your child can fit only one finger between the strap and their chin. Slide the side adjusters up or down until the V sits under the ear, not in front of it or behind it.

Then buckle the chin strap and tighten it. A common mistake is leaving the chin strap loose because it feels comfortable; a loose strap lets the helmet rotate or fly off in a fall. When your child opens their mouth wide, they should feel the helmet press down gently on the top of their head.

• Checkpoint: straps should not twist. Run a finger along each one to flatten it.
• Trim or tuck excess strap so it cannot catch on clothing or the bike frame.

Step 4: Run the shake and push tests

With the helmet buckled, have your child shake their head side to side and nod firmly. The helmet should stay in place with only minor movement, and the front edge should not lift to expose the forehead. Then place your palm on the front of the helmet and push upward gently; if the helmet slides back easily, tighten the dial or shorten the chin strap.

Finish with a real-world check: have your child walk, then sit on their bike or scooter and look over both shoulders. The helmet should stay put and not block their view. If it shifts during normal movement, repeat steps two and three rather than accepting a compromise.

• Mistake to avoid: testing fit while the helmet is unbuckled.
• If the helmet moves more than slightly in the shake test, it will not stay put in a fall.

Step 5: Know when the size is wrong, not just the fit

Sometimes no amount of adjusting works. If the dial is at its tightest and the helmet still slides, it is too big. If the helmet sits on top of the head like a cap and cannot come down level, it is too small or the wrong shape for your child's head. In both cases, changing the size is the fix, not tightening harder.

Check the size range printed inside the helmet against your child's head circumference, measured just above the ears and around the widest part of the back of the head. A helmet that fits correctly should need only moderate dial tension, and your child should forget about it within a few minutes of riding.

• Measure the head, then compare to the stated size range before buying a replacement.
• A helmet that needs daily re-tightening is usually the wrong size, not a faulty dial.

Helmet fit check in five steps

1. Set the position: Place the helmet level with the front edge two fingers above the eyebrows. Checkpoint: the forehead is covered when your child looks up.
2. Tighten the dial: Turn the rear dial until the helmet moves the scalp when your child raises their eyebrows. Mistake: overtightening to make up for long straps.
3. Form the ear V: Slide the side adjusters so the straps meet in a V just below each earlobe. Checkpoint: no twisted straps and no strap in front of the ear.
4. Set the chin strap: Tighten until only one finger fits between strap and chin, then buckle. Mistake: leaving it loose because it feels comfortable.
5. Test and recheck: Shake the head, push up on the front rim, and look over both shoulders. If it shifts, go back to the dial and straps before riding.

Helmet details that affect fit

• BANWOOD ECO HELMET - IVORY (50-54 cm): Made with a recycled ABS shell and EPS foam liner, certified to EN 1078 and CPSC standards, in a 50-54 cm size. The 50-54 cm range covers a wide age span, so the rear dial and strap adjusters do most of the work of keeping the fit stable as your child grows.
• BANWOOD ECO HELMET - LAVENDER (50-54 cm): Same ECO Helmet construction and certification in a lavender colorway, 50-54 cm. If your child is between sizes, the same shell in either color fits identically, so choose by style rather than by fit.

A correct helmet fit is not a one-time job. Run this five-step check before the first ride of the season and again after growth spurts or haircuts. It takes less time than finding the bike pump, and it is the difference between a helmet that is certified and a helmet that actually protects.