I disagree with getting a larger size on these,i am a size 8-81/2 and i got a pair of these brought over from Canada ,they have a 10mm liner and are marked a UK 8 ,they are a bit big on my foot ,so maybe a 13mm liner would be better for me.in my experience this type of pack boots are oversized ,i also bought a pair of lacrosse leather lace up pack boots and went with the getting a size bigger theory and the were huge on my foot.i am pretty sure my Sorel pac boots would have fitted me better in the next size down better than the correct size.To sum up if possible buy this type of boot (especially)or any footwear as a matter of fact in the store and try them on properly,there is nothing worse than ill fitting footwear especially when you spend a small fortune on them.