I wear a US size 11 so I ordered the Large boots as some other reviewers suggested, and I'm glad I did. They are just a tad large but fit okay once I put in my orthotics (inserts customized to my feet). Others may wish to add a gel insert and/or wear thick socks. I've worn them for an hour now and my feet aren't complaining. Don't know how long they'll last, but I will probably only wear them about three times a year so they should be fine. I'm 5'11" and the boot tops come to 4.5 inches below my knee caps, so knee length britches wouldn't work for me, but I have no problem stuffing my full length "pirate pants" inside the boots. Glad I have some footwear for my pirate costume!