Please order in American sizes, and keep in mind the sizing tips within each brand; 

Note 
" To ensure none, or very little heel slippage for dancing, we have made the throat of the boot a little difficult to get into. Have patience and use a plastic bag if necessary to get into the boot at first . Once you are in the boot, the fit should be OK and the boot snug on the heel. If the plastic bag was needed, take the boot on and off a few times, then you should be able to get into it without the plastic bag.