I ordered an 8 online because I'm generally an 8 in US sizes, but sometimes I'm a 7.5 and since they don't sell half sizes, I thought and 8 would be perfect. The 8 was too big. So I went to the store to return them and tried on a 7 and it was perfect! So if you're a half size I would recommend sizing down. Or even if you're a full size I would still size down just in case, because they are pretty big. They're warm with the fleece socks and comfortable overall.
this is second pair for my daughter - she loves them. the first pair still looks like new after a year- much better quality than the average rain boot. She just wants another color. She wears on college campus all the time so they have to be comfortable to walk. Fits as normal size.