I am a plus size lady and a little self-conscious about my upper body, so if the fabric has a lot of stretch, I will buy a size up because I don't want it to cling to me and accentuate my upper body and other flaws. So I ordered a 16W and oh my goodness! With the right underwear, this dress is a hit! This dress does have a lot of stretch. Makes this simple dress more elegant. Will definitely buy again.