I live in the northeast and have been wearing Acorn fleece socks for years.  I love the socks, they are the only ones that keep my feet nice and warm during the long cold winter months.
I ordered four pair this past week and followed the sizing chart.  My first two pair arrived today and they are huge.  It looked like the chart said that I should be a US women's medium, but I should be a small. My shoe size is a 7B.
Fortunately the two pair that came today can be used by male or female and I will give these two pair to my grandson who would fit into this medium.
My next two pair, which are still being shipped, are most definitely for a female and I will have to return them because there is nobody in the family who can wear them.
Again, the socks are great, they are warm and comfy and I would recommend them for anybody looking to keep their feet nice and warm.