What Size Shoes Should I Buy for a Child With Orthotics?

When your child wears an orthotic device inside their shoe, it adds volume. The device raises the foot, takes up depth, and changes the amount of internal space available. A shoe that fits perfectly without an orthotic may be too tight, too shallow, or simply impossible to fasten once the device is in place.

This means you will almost always need to buy a larger size than your child's measured foot length suggests. How much larger depends on the type of orthotic device.

The amount of extra room your child needs depends on the thickness and profile of the orthotic device. Use the following table as a starting point:

Orthotic Type	How Much Bigger
Thin over-the-counter insole	Half a size up
Standard custom orthotic	One full size up
Thick or highly contoured custom orthotic	One to one-and-a-half sizes up
AFO (ankle-foot orthosis)	At least one full size up, sometimes more

These are guidelines, not rules. The only reliable way to confirm the size is to bring the orthotic to the shop and have your child try the shoe with the device in place.

If your child wears an orthotic on only one foot, you need to size for the foot with the orthotic. That foot needs the extra room, and both shoes must come from the same pair.

On the non-orthotic foot, you can adjust the lacing or Velcro to snug the shoe more tightly around the instep. This compensates for the slight extra room on that side.

If the size difference is significant, ask about split-size purchasing at specialist children's shoe retailers. Some retailers will sell two different sizes as a pair, which can make a real difference to comfort and fit.

Going up a size to accommodate the orthotic can sometimes introduce heel slip, where the foot lifts out of the shoe at the back with each step. This is uncomfortable, causes blisters, and prevents the orthotic from working properly. To reduce heel slip:

• Choose shoes with a well-padded heel collar: the padding around the top of the heel cup grips the foot and reduces movement.
• Check for firm heel counters: squeeze the back of the shoe between your thumb and finger. It should resist compression and hold its shape. This is the squeeze test, and it is one of the most important checks you can do.
• Use laces or Velcro to snug the instep: the fastening across the midfoot is what locks the heel down into the shoe. Tighten it enough to prevent lift without restricting circulation.

When measuring your child's feet for orthotic-compatible shoes, follow these steps:

• Measure with the orthotic inside the sock. Your child should be wearing the socks they will normally wear with the shoes, and the orthotic should be in place under the foot.
• Measure with full weight on both feet. Your child should be standing, not sitting. Feet spread under body weight, and you need to capture that fuller measurement.
• Measure both feet. It is common for children's feet to be slightly different sizes. Always size for the larger foot (or the foot with the orthotic if only one foot is affected).
• Bring the orthotics to specialist appointments. If you are having your child fitted at a specialist retailer, the fitter will need the device to assess fit accurately.

Children's feet grow approximately two sizes per year between the ages of 3 and 10. This growth can happen in sudden spurts rather than gradually, so shoes that fit well today may be too small within a few weeks.

For young children during peak growth years, check the fit monthly. A quick two-minute check with the orthotic in place will tell you whether the shoes still have adequate room. Press your thumb above the big toe while your child is standing. There should be roughly a thumb's width of space between the longest toe and the end of the shoe.

If you notice the shoes are getting tight, do not wait. Shoes that are too small will prevent the orthotic from sitting correctly and can cause pain, blisters, and pressure injuries.

Should I buy the current size or the next size up to allow for growth?

With the orthotic in place, aim for approximately a thumb's width of growing room between the longest toe and the end of the shoe. This provides some room for growth without the shoe being so large that the foot slides around inside it. More growing room than that increases the risk of tripping and prevents the orthotic from sitting in the correct position.

My child's orthotic is very thick and I cannot find shoes that fit. What should I do?

Ask your child's orthotist for a referral to a specialist paediatric fitting service. These services stock extra-depth shoes designed specifically for thicker devices and AFOs. Read our guide on where to buy children's orthotic shoes in the UK for more options.

Can I rely on online size charts?

Online size charts are a useful starting point, but they cannot account for the volume added by your child's specific orthotic device. Always try the shoe with the orthotic in place before committing, whether that means buying from a physical shop or ordering online with a returns policy.

My child has just gone up a shoe size. Do the orthotics still fit?

Not necessarily. If your child's foot has grown significantly, the orthotic may no longer be positioned correctly relative to the arch, heel, and forefoot. Contact the orthotics department to discuss whether the device needs reviewing or replacing.

Looking for the adult version of this guide? Read What Shoe Size Should I Buy With Orthotics?

Browse our full Children's Orthotic Shoe Buyer Guide