These boots are very generously sized. We have found from feedback from our customers that you may need to go down at least one shoe size. For example if your child is normally a UK Size 4 we would suggest UK Size 3. We suggest that you order a size lower than you would usually as these are a large fitting boot. ( We would advise you not to go an extra size up to allow for "growing room" as the boots are very generoulsy sized and you would end up with a pair of boots 2 sizes too big for your young farmer or "handy man or woman".