These coats fit large. I normally wear an 8 and I found that I needed a 6 for the fall.In the winter, the 8 fit well as I had a long sleeve shirt and a sweater underneath.
2 Styles are Petites, the Ruby Pea Coat & the Blue Pea Coat. They fit truer to size. I am wearing the 6 in those coats and have a sweater underneath.
Go down a size if you like a fitted look. Stay your regular size if you like to wear a sweater underneath and have lots of room to move.