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wrong bra size

You’ve probably heard the oft-cited claim that 80% of women are wearing the wrong bra size. That’s probably not true. It’s based on three studies done between 1999 and 2008, but with sample sizes of between only 30 and 103 women, they can hardly be expected to be representative of the entire world, or even a country. Plus, we’ve come a long way in terms of bra fit education and size variety since 2008.

And yet, a lot of women are wearing a size that’s not optimal. Perhaps not 80%, but a fair few nonetheless. Just ask any bra fitter – they’ll tell you that most women leave the boutique with a bra that’s a size different to the one they came in wearing.

So why is it so common to get your own bra size wrong? We don’t wear shoes that are too big or dresses that are too small, so what makes bras any different? Well, as it turns out, a few things.

You don’t have a right size

It’s definitely possible to wear a wrong bra size. I usually wear a 30DD – put me in a 34B and it’s not even going to come close to fitting. However, I have plenty of bras in sizes such as 32C, 32D and 28E that do fit me well.

We don’t have one ‘true’ bra size. It’s completely normal to find your best fit in different sizes based on the brand, the style, and even the time of the month – breasts can swell and shrink with hormonal fluctuations.

Part of the reason that you can’t compare bra fit to the fit of a dress or top is that bras require so much more precision. Variations of as little as a few millimetres when designing and sewing a cup’s panels can change the fit, so it’s no wonder there’s very little consistency between brands. Here is an in-depth explanation of why you don’t wear the same size in every bra brand, if you’re interested in learning more.

So when you get fitted for a bra and are told you need a 34D, remember, you need a 34D in that bra. There is a good chance you’ll also need a 34D in another, making it the best place to start when picking one up to try on, but it’s not a sure thing.

Bra sizing is confusing

Or at least, that is what a lot of us believe. However, this is only because there’s still not enough education on the topic. It’s not something we learn in school, and a lot of the time it’s not something we were taught at home by our mothers either.

This leads to a lot of misinformation, and often, people don’t even know how a bra is supposed to fit. For example, did you know that the band needs to be fairly firm because that’s what’s supporting your breasts, not the shoulder straps?

Understanding bra fit is actually not that complicated. If you read this list of 4 steps to check that a bra is fitting well plus this explanation of sister sizing, then you’ll already know enough to judge the fit of the bra in the changing room and pick out which size to try next if the first one’s not quite right.

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

A lack of size variety in stores

You’re much more likely to be wearing the wrong size if the one you really need is not a ‘core’ one, i.e. not in the 32-38 A-D range that most brands and popular lingerie stores typically focus on.

If all you ever see is A-D cups, then it’s understandable if you just assume that you must be one of those sizes. You may not even realise that there’s an alternative, that bra band sizes actually go as low as a 26 and as high as 50+!

One of the most common bra fit problems is wearing a band that’s too big. That’s probably because many women will try on the largest cup size in store, find them too small, and mistakenly think the solution is to try a larger band size because, well, they can’t go any higher in the cup size so what else to do?

Stigma surrounding large cup sizes

Linked to the above point, because A-D cups are what is most commonly available, those can feel like ‘normal’ sizes and therefore anything higher, abnormal. Some women just don’t want to be a large cup size, especially when there are cartoons floating around online saying things like “E is for Enormous, F is for Fake…”.

The truth is that a cup size on its own is meaningless. The cups on a 32F and a 38F are not the same size, and wearing a D-cup or above doesn’t automatically mean that you have ‘huge’ boobs. And if you need an F cup, or a G, or a J, so what? You don’t have to tell anyone what’s written on the label of you bra if you don’t want to!

Lack of regular fittings

When did you last have a bra fitting? You’ll be in the majority if your answer is “quite some time ago”. Perhaps the reason that so many women who get bra fittings find out they need a different size, is because only those who are experiencing discomfort due to wearing the wrong size are the ones who prioritise it!

However, the longer it’s been since your last professional fitting, the higher the chance you could find a better size. Our breasts don’t reach their final size post-puberty and stay that way forever. Age, weight loss, weight gain, pregnancy and a new exercise regime are just some of the things that can cause a change, and you’ll wear a variety of bra sizes over your lifetime.

So don’t assume that you need a 34C just because that’s what you’ve always worn. Have a fitting every 6-12 months, and you may be surprised by what you’re told!

Related: What Is A Bra Fitting?

how do you know if your bra fits

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!

If you used to wear a size that was wrong and have since discovered a better fit, what do you think is the reason you didn’t find it out sooner? Share with us in the comments below!

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Published by

Estelle Puleston

Estelle Puleston is the founder of, a blog dedicated to her love of lingerie. She works full-time as a copywriter and digital marketer for the lingerie and swimwear industry, and when she’s not doing that, she’s probably sewing or enjoying a good cup of tea.

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