B Cup Bras

What is a B Cup Bra?

Cup size, the letter attached to your bra size, represents the difference in measurement between your bust and band. For B cups specifically, this means there's an approximate 2 inch difference between your bust and band measurements.

Many of us identify strongly with "being a B cup" (or any specific size), but your true cup size actually depends on your band measurement too. This relationship means your cup size naturally fluctuates with your body's monthly changes or as your body evolves over time. It's also perfectly normal to wear different cup sizes across brands, as sizing standards vary between manufacturers.

Choosing the right B Cup bra

First, confirm your bra size using our bra size calculator. Next, choose the bra style that best fits your lifestyle and needs as a B cup size.

How should a B Cup Bra fit?

Your B cup fits perfectly when breast tissue fills the cup completely without overflow or empty spaces. When cups run small, tissue escapes from the top or sides, often leaving uncomfortable red marks on skin. Conversely, cups that are too large create noticeable gaps where your natural shape doesn't meet the fabric, resulting in an uneven silhouette under clothing. The ideal fit creates a smooth transition from cup to body with no visible fit issues.