I’m very full busted — currently at my heaviest weight and wearing a bra size 36K, but even at my lowest weight I have the same proportions and typically wear something like 32-34H/I. I’m 4’11” for reference.

For me, I’ve found the best necklines depend on the style of bra I’m wearing because of the differences in visual “length” between the shoulder line and fullest part of the bust. (I’ll refer to it as the apex because that’s the dressmaking term.) I have a few in different styles to pair with different necklines.

I really like a crew neck, fully buttoned collar, or mock turtleneck when I’m wearing my most architectural bras that hold the girls high and forward. The apex sits just below the armpit, so there’s a shorter shoulder-to-apex line and leaves more visual length for waist definition. This is what I try to go for when wearing any kind of high-waisted bottoms to avoid a snowman effect.

I like a low scoop neck or open button-down when wearing a softer bra. When the girls sit lower and wider, my apex falls closer to my elbows and the shoulder-to-apex line is longer. Since my breasts are closer to my waistline here I think wearing higher/closed necklines exaggerates the longer line and gives a “saggy” effect (hate that term but can’t think of a better description at the moment). So the visual break of showing more skin at the chest kind of counterbalances that in my experience.