I ordered the first one of these Amazon Essentials cardigans in size Medium as suggested by the size chart, and it was too small which surprised me since I am only 5'6" and 145 lbs. Interestingly, some of the reviews before I made my size choice said they ran small, some said the size was correct and others said they ran large. Obviously, the issue must be that size satisfaction depends on how one likes their clothes to fit. Thus, maybe the following will help in your choice of size for this cardigan. I like a loose fit in a cardigan because I like to be able put it on or take it off with ease when I get too cold or to warm when I am watching TV, sitting at my desk, while eating, etc. That means a good size for me is a cardigan that has roomy sleeves that don't impede my taking the cardigan off or putting it on while I'm wearing a long sleeve shirt or sweater under it. For me, the large fits the bill. I also don't like cardigans that bind across the chest and under the arms. Again, the large size fits the bill. I hope that helps some. BTW, I am really impressed by the quality of the Amazon Essentials cardigan. It's attractive, appears to be relatively well made, and is remarkably reasonable in price. In fact the price at around $20 is so reasonable that I'm keeping the medium as a backup rather than returning it.