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do bra sizes vary by brand

You’ve probably been handed various bras to try on after a bra fitting. Have you ever been given a bra that’s not the size the bra fitting suggested? You were probably wondering why you were even measured if you’re not going to try on that size. But to your surprise, the bra fits. And it fits well.

What?! You ask yourself, “Is it normal to wear more than one bra size?” Yes, it’s completely normal for more than one bra size to fit! Many women have different sized bras in their lingerie drawer. And, they can easily go from bra to bra without noticing a difference in the fit.

We’re going to explain why women can wear different bra sizes and why it’s absolutely fine. Read on!

Understanding how bra sizes work:

Understanding how bra sizes work helps you also understand why more than one bra size may fit. You know that a bra size comes down to two things – the cups and the band. Measurements of the circumference of your ribcage and your bust are taken to get these two sizes. But, did you also know that the cup size doesn’t remain the same as the band size increases? Hence why, let’s say, a 34B looks different than a 38B. The cup size – though still technically a B-cup – must change slightly to accommodate the band size. The majority of a bra’s support comes from the band. However, the cups must adjust to the band size to help provide adequate support.

Related: Bra Sizing Explained: Here’s How Bra Sizing Works

Your bra size has a sister size.

Your bra sister size can hold a similar volume of breast tissue in the cups. And, sister sizing is why two different bra sizes may fit.  We mentioned above that the cup size increases when the band size increases – though the cup size remains the same letter cup size. This is so the cups can hold more volume. So, if you wear a 36C, your bra sister size would be a 38B. The cup size increases and the band size decreases, resulting in a similar cup volume.

Knowing your bra sister size is super helpful when bra shopping. You can find your sister size if a store is out of stock in your size, or if your size doesn’t feel quite right.

Different brands may fit you differently.

Two different bras that are the same exact size may fit differently. This is because the fit can vary by brand and by fabric type. You may wear a 32B in one brand, yet find that a 32B in another brand is too snug on your breasts. This is where knowing your sister size comes in handy. The small adjustment in your sister size may be just what you need for the bra to fit well.

While it’s totally normal for more than one bra size to fit, it’s important to always know your true bra size. We suggest starting every bra shopping trip with a bra fitting. Your bra size may have changed for a variety of reasons, and a fitting ensures you’ll find the right fit. Once you know your measurements, you can easily test out bra sister sizes and feel confident that you’re making the right sizing choice.

Related: Why Don’t I Wear The Same Size In Every Brand?

We Highly Recommend

Whether you’re shopping for new everyday bras or lingerie for a special occasion, it’s always a good idea to seek out a second opinion. We know how hard it is to find bras that fit well and feel good, especially when you’re doing it on your own. If you’ve ever felt unsure about your bra size or you just don’t know where to go to find good bras, it’s time to let a bra fitter help.

Many specialty lingerie boutiques offer bra fittings. Their expert bra fitters will take the pain and frustration out of bra shopping and do all the work for you. Even better, their product knowledge can save you time and money. Plus, they know where all of the best bras are hiding.

If you’ve struggled with finding bras in the right size, it’s time to make a change. Visit our specialty store locator to find a store near you and schedule an appointment.

Happy bra shopping!

Featured image lingerie:
Parfait Marion Contour Padded Bra P5391 | Parfait Marion Hipster P5395 in Pink Parfait
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Lauren Hamilton

Lauren Hamilton is the founder of, a lifestyle and relationship blog offering relationship advice and encouraging women to be the happiest, most confident version of themselves through positivity and self-love. She's also a freelance writer and communications strategist. Follow her on Instagram or Twitter, and check out some of her accomplishments on her portfolio.

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