I am a perfect American 8, which in my opinion is a UK 13. Landsend call it a 12. Either way it fits me perfectly, as do other makes of size 8 trousers from US companies. However these 'off white' jeans wouldn't even do up. Far too small, more like a UK 8. It's not me, as I bought another style of trouser in a size 8 at the same time and they fit like a glove. If you are used to Landsend sizing you will need to go up at least one size. Also, unlike another reviewer, I found these very short for a 25" inside leg. Cropped trousers are usually almost full length on me, as I'm only 5'3" tall.