80% of Women are Wearing the Wrong Bra Size. Are You?

ThirdLove models wearing the bestselling 24/7å¨ T-Shirt Bra in different colors.

Finding a bra that fits you shouldn’t be a tall order. The truth is most bras aren’t designed to fit the way they should. Good news? It’s not you — it’s the bra. So we design better bras to make you look and feel great in every outfit. Regarding fit, we have style options for every breast shape: strapless, full coverage, plunge, wireless, and more. If you’re not sure what shape breasts you have or which styles you should try, check out our boob shape dictionary here.

So you’ve found a few styles you like, but know that we’re the only bra company out there with half-cup sizes. Are you a full cup size, or have you always been a little more in between? If you’re dying to know and can’t wait, take our Fitting Room Quiz. It was created by expert bra designers who know exactly what slipping straps or gaping cups mean. We’ll talk more about what the tells of knowing you’re wearing the wrong bra size and how to get the right fit.


How Do You Know If You’re Wearing the Wrong Bra Size?

If you’ve taken our quiz you now have a better idea of what to pay attention to when checking your fit. If you’re new to ThirdLove, here are a few things that we talked about in the quiz: slipping bra straps, gaping cups, spilling over your cups, the way your waistband sits, and down to what hook you should start with. Because over 80% of women are wearing the wrong bra size (right now, as we talk about it), we thought every woman should know about it and how to fix it.

3 Ways to Check Your Fit

  1. Which hook are you on? When you put on your bra, you want to start at the last hook, and the band should hug your body comfortably. If you have to go to the first hook, your band size is likely too big, and you should go down a band size. We say start on the last hook because your bra is new and will stretch over time. So you’ll eventually get to that hook on an older bra, but it shouldn’t be where you start.
  2. Your waistband: When you put the bra around you and clasp the last hook, the waistband should fit snugly. When we say snug, we don’t mean tight. You should still be able to put about two fingers under the band. Try it now, we’ll wait. If you can’t get two fingers under there, getting one in shouldn’t be too hard. If so, you may need to go up a band size. Sometimes, you might spill over the sizes of your waistband, which could mean you need to size up in the band.
  3. Cups: Your breast should fit nicely in the cup and fit it completely and contour your natural curve and shape. If you see quite a bit of space left in the cup, you feel any digging in, or you’re overflowing out of it, it’s either too small or too big. Wire sitting on your breasts or riding up throughout the day, so that’s where it ends up? Your cups are probably too small. So once you’ve gone down a cup, you should feel that smooth, snug fit. Think you might need a half cup? Contact a Fit Stylist to see if you need a half-cup size.


Common Bra Size Myths

Seeing how many women wear the wrong bra size, it's time to separate the facts from the fiction and help you make the best bra-buying decision. Despite being the foundation of every woman's wardrobe, bras are shrouded in misconceptions and urban legends that often lead to improper fit. Whether they are old wives' tales or well-meaning advice passed down through the generations, it's time to end these bra-size myths.

Myth: Once you are an adult, your bra size never changes.

Reality: Our bodies change throughout our lives, so getting refitted occasionally is important, especially after weight fluctuations or pregnancy.

Myth: Loose-fitted bras are the most comfortable

Reality: Comfort comes from a well-fitted bra. Wearing the wrong bra size can lead to a lack of support and discomfort.

Myth: There's only one standard bra size for you.

Reality: Many women fall between standard bra sizes. That's where ThirdLove's half-cup sizes come in. They provide a more precise fit. 

Myth: 34D and 36D have the same cup size.

Reality: A bra cup size is relative to the band size. This means that a larger C cup holds more volume on a smaller band than the same C cup. This also means that there are “sister sizes” - bras that hold the same volume of breasts despite having different sizes. For example, a 36C cup holds the same volume of breast tissue as 34D or 38B. So, if you find that the cups of 36C cup fits you well, but the band is too small or loose, try your sister sizes.

Myth: All bras fit the same.

Reality: While they may be close, each brand has unique design standards. A particular size from one brand might not fit as well as a bra in the same size from another. At ThirdLove, you can always count on us to offer consistent quality and standards, no matter the style.


Importance of a Proper Fitting Bra

Why is a proper fitting bra so crucial, you ask? First and foremost, comfort. When you wear the right size bra, you're ensuring that you are supported with no digging in and poking or bra straps slipping off. Additionally, a bra that fits well supports your breasts correctly, reducing strain on your back, shoulders, and neck. This can prevent pain and discomfort, especially for women with large breasts.

A well-fitted bra also improves your posture. When your breasts are adequately supported, you're less likely to slouch or hunch forward, leading to better spinal alignment and reduced tension. 

In addition to physical benefits, the aesthetic appeal is undeniable. The right bra enhances your natural shape, providing a smooth silhouette. It's the secret weapon behind every stunning outfit. No more odd bulges or gaps–just you, perfectly proportioned. You can strut your stuff; you know you look fabulous!

Moreover, the right bra, whether a good sports bra for the gym or a good T-shirt bra for the office, increases productivity. You can easily focus on your work or workout when you are well-supported.


So What Happens If You Wear a Bra That Just Doesn’t Fit?

Wearing a bra that doesn’t fit quite right can cause unnecessary stress on your body. We’ll talk through a few of them. Regardless of your cup size, any bra that doesn’t fit properly will be uncomfortable. When you have heavier breasts, a bad fit means that heaviness isn’t balanced and can create issues.

Breast Pain

If your underwire is cutting into the sides of your breast, you may notice bruising and an extra pull on your skin. If your cups aren’t fitting comfortably around your breasts to give them support then you’re leaving the support to your breast tissue itself. Creating stress on your tissue and causing stretch where it doesn’t necessarily need to happen. Stretch can mean sagging over time, especially if you’re getting that support with a bra made for your size.

When you’re in the right bra size, you won’t feel any of this added stress on your breast tissue. The best bras are one you don’t feel like you’re actually wearing all day. In fact, we created a line of bras specifically made for everyday all day: our 24/7® bras. Check out our T-Shirt Bra, you’re going to love it. Fits just right, made to make you look and feel great no matter what.

Shoulder, Neck & Back Pain

Your waistband is where a large amount of the support you need comes from. Your bra is made with multiple components that are designed to work together to support and hold your breasts. If your bra’s waistband isn’t snuggly fit, your straps or cups may be doing more work than they should.

You might feel back, neck, and shoulder pain set in when you’re hunching over more because you’re not getting the needed hold. This is the most uncomfortable kind of pain that tends to build over time. So get that badly fit bra off your back and get one on that supports your breasts properly.


Find Your Perfect Fit

Now that you understand the pitfalls of an improper fit and the transformative power of the right bra size, it's time to experience the ThirdLove difference. Our range includes options for every occasion, from everyday wear to special events. Whether you need a strapless bra for a chic evening dress, a wireless bra for ultimate comfort, or a plunge bra for that perfect neckline, we have you covered and in an extensive size range.

ThirdLove offers a variety of tools and resources to help you discover the ideal bra for your unique shape and size. Maybe you are wondering, "What is my bra size?" Enter the innovative online fitting room. Answer a few questions to discover your size and get personalized bra recommendations.

In addition to our Online Fitting Room, ThirdLove offers the convenience of in-store fittings. Visit any of our stores to get personalized assistance from our fit specialist.

We’re here to help if you have any questions. If you have a question, send us a direct message on Instagram at @ThirdLove.