40B Bra Size

What is a 40B bra?

Your cup size, shown by the letter in your bra measurement, reflects the difference between your bust and band measurements. For a B cup, your bust is roughly 2 inches larger than your band or underbust measurement.

Your band size — the number in your bra size, like the “38” in 38B — measures the circumference around your ribcage, just beneath your bust. The band is what provides most of your bra’s support, while the straps offer more minimal lift.

That’s why finding the right band size is essential for both comfort and stability.

Key bra features for 40B bra size

For a 40B bra size, there are many styles that will be compatible with your cup and band size. If your goal is to enhance your shape and cleavage, consider bras with sturdy foam cups and padding.

If comfort is your top priority, we recommend wireless bras with bonded support. Wireless bras, unlike bralettes, have more support features and smoothing benefits that 40B bra sizes will enjoy.

If you wear a larger band size, choose bras with wide, smoothing wings and a thoughtfully designed back that helps reduce bulging and create a sleek, seamless look.

Ideal fit for a B cup bra

For someone with a B cup, the ideal bra fit focuses on balanced support, smooth shaping, and a natural lift. The cups should enhance your shape without creating gaps or causing any overflow.

The band should provide most of the support. It should feel snug but not tight (you should be able to fit two fingers underneath it comfortably).

The cups should lie flat against your chest, with no gaping, wrinkling, or spillage along the edges. The center gore (the middle part of the bra) should sit flat against your sternum for optimal support and alignment.

For B cups, look for medium-set straps and cups that follow your natural contour to maintain lift and prevent slipping or digging.

Choosing the right 40B bra

First, use our bra size calculator to confirm you’re a 40B size. Once you’ve verified your fit, consider your top priorities as a B cup and choose a style that best supports your needs.

Shop Honeylove B cup bras