I typically wear a XL in dresses, have a 40F bust size and the 1X in this fitted top fits beautifully, but theres no wiggle room in the chest for me. This dress has no stretch in the top area. Just FYI, that fitting a 1X in this dress doesn't mean that's your fitted dress size on this site; sadly a 1X in another fitted dress wasn't the right fit. Keep an eye on the reviews to give you a better idea. In smocked dresses, XL is my go to and fits perfectly for me. Hope this helps!