How to Size Kids' Shoes to Fit Over an AFO

Sizing shoes for a child who wears an ankle-foot orthosis (AFO) is different from sizing for a bare foot. The brace adds length, width, and depth, and the shoe has to hold both the foot and the AFO without squeezing. Here's how to get it right.

Why a braced foot needs a different size

An AFO wraps the foot and ankle in rigid plastic, often with padding and straps. That adds volume everywhere - especially length at the heel and depth over the instep. A shoe that fits your child barefoot will almost always be too small once the brace is on. Most kids in AFOs go up at least one size, and many need a wider width as well.

Step by step

• Fit with the brace on. Always size with the AFO actually worn, not estimated. Bring it to every fitting.
• Start a size up. Begin about one full size above your child's barefoot size, then adjust from there.
• Use the depth. Remove one insole layer to free up room for the brace - shoes like BILLY's come with multiple removable insoles for exactly this.
• Check the toe. With the brace fully seated and the shoe fastened, press for about a thumb's width of space at the longest toe.
• Check width and heel. The upper should close without straining over the brace, and the heel shouldn't gap or pop out when your child walks.

Width matters as much as length

Many parents size up in length but forget width. A braced foot is wider, and an upper stretched tight over an AFO creates pressure points. BILLY's Classic D|R II comes in Medium, Wide, and Extra-Wide (MDR, WDR, XDR), and the Goat adds a wedge insert for even more internal room. Browse the full range in Kids' AFO Shoes or our Wide & Extra-Wide collection.

When to involve your orthotist

Your child's orthotist knows the brace's exact dimensions and can tell you how much room it needs - they're the best resource when you're between sizes or fitting a new AFO. For more on getting shoes on once they fit, see our guide to putting shoes on over a brace, and our overview of shoes that fit over AFOs.