How to Tell If You're Wearing the Wrong Bra Size (Hint: You Probably Are)

We all know finding the perfect-fitting bra can be a tricky proposition, but it doesn't have to be. Lingerie expert Kimmay Caldwell is here to de-mystify the process and explain how you should choose your next bra so that it makes "the girls" look their best and keeps you comfortable all day long.

"You can't just go to a store and pick a bra off the rack and say, 'It's my size, it's going to fit!' Same thing with jeans, same thing with bras," she says.

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She explains that your bra size is going to depend on how tightly you need the band to fit against your rib cage. And the band size is directly related to the cup size when it comes to the volume the bra can hold. For example, she says, "If you need the strap to be tighter, you might need to go down a band size, which would then make you go up a cup size."

If this still sounds a little confusing to you, check out Kimmay's solutions for three real-life bra quandaries:

Problem 1: Strap Digging Into Back, Spilling Out of Cups

Aisha recently lost 80 pounds and was having trouble with her bra's fit — the strap was digging into her back and she was spilling out of the cups. Kimmay pointed out that the back strap was too thin, and set her up with a bra that has more coverage and a wider band in the back, so it won't dig into her skin. She also moved her up from a 32D to a 32E.

Pro Tip: "The back of your bra is responsible for 90 percent of the support, so this has to be nice and snug," Kimmay says.

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Problem 2: Underwire Digging In + Not Enough Coverage

Our viewer Faye was wearing a bra that was too big in the band and too little in the cups, and the underwire dug into her ribs. Kimmay changed her size from a 36B to a 34D, plus gave her a bra with a new technology — a flexible underwire.

Faye's sizing discrepancy isn't unusual. Kimmay says, "About 90 percent of women I help are one cup size too small and one band size too big."

Problem 3: Slipping Straps

Our third viewer, Fortune, is really petite and her 30F bra straps just wouldn't stay up. Kimmay set her up with a new bra in the same size, but added a clip at the back to make her straps into a racerback shape and therefore less likely to slip.

Pro Tip: When you store your bras, do not fold them! This could damage the moldable cups. Kimmay recommends storing them piled on top of each other, or keeping them in a special plastic bra-stacking device.

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