How Should a Bra Fit? We Explain How To Tell If Your Bra Fits Correctly

Renata Black, EBY Co-Founder & CEO

A badly fitting bra can hold you back in life. From feeling comfortable whilst exercising to feeling confident throughout the day, a bra should never have to cause discomfort or pain.

At EBY, we are strong believers that your underwear should never hold you back, and the war against bad bras has gone on for far too long. In fact, a survey by Debenhams shows that women tend to keep their bra for five years on average, with approximately one-third of this survey group never having been appropriately fitted in the first place!

Ill-fitting bras lead to a host of problems that include breast pain, back pain, discomfort, and inadequate support. Furthermore, these bras can also be painful to wear due to straps digging into the shoulders or slipping off.

In this guide, we will help you to identify the key signs that your bra doesn’t fit you anymore, and how you can tell when you’ve found the perfect fitting bra.

Signs Your Bra Doesn’t Fit You

There are several characteristics of an ill-fitting bra. Generally, if your bra is causing you any type of pain or discomfort, this typically means that it does not fit you properly. Look out for these following signals when you next wear or try on a bra!

 The Band is Too Tight or Too Loose

If the band of the bra is not the right size, it will either be too tight or too loose around your body. If this fit is uncomfortable, it usually also signifies that your cup size is not the right fit either! A longer band is best for those with a wider body type and a shorter band is more beneficial for supporting more petite frames.

Straps are Digging Into Your Skin

Wearing the wrong size bra can leave painful red marks on your skin where the straps have been digging in. This pain can make wearing a bra a negative experience when we believe it should be empowering. If your bra straps are digging into your skin, this usually means that the cup is slightly too big. This happens as you try to compensate for the lack of cup support with the strap, tightening it to feel enough support over the breast tissue area.

Try decreasing your cup size to feel snug around the breasts as well as the shoulder straps. You should aim to be able to comfortably yet firmly fit at least 2 fingers underneath the strap.

Underwire is Digging In

This pain can cause extreme discomfort and redness to your delicate skin. If your bra underwire is digging into your rib cage area or slightly below the breast, it is highly likely that your bra is too tight. We would recommend trying to go down a bra band to see if this feels more comfortable. If it doesn’t, then your cup size is probably too small too!

Chafed Skin

Chafed skin can be confusing as it can happen if your bra is both too tight or too loose. Chafed skin can be sore to the touch for a few days, making it uncomfortable to wear a bra again – even if the next bra fits well! Therefore, it is very important to make sure your bra fits comfortably. 

Upper Body Pain

Upper body pain can be caused by ill-fitting bras and is especially common in women with a bigger cup size. Neck pain, back pain, and cramping in your shoulders are all typical examples of upper body pain caused by wearing the wrong bra size.

Cup Spillage

Cup spillage is when some of your breasts do not quite fit into the bra cup due to the cup size being too small. For those who prefer a modest bra look, cup spillage may make you feel insecure in your body.

Cups Gauge  

Cup gaps mean that your bra does not fit comfortably over your entire breast area, and you will need to look at getting a smaller cup to improve this.

How Should a Bra Fit - EBY

How Should Your Bra Fit- All Four Parts Should Fit In Unison! 

Did you know that up to 80% of women are wearing incorrectly sized bras, with 70% wearing too small and the other 10% too big? This section will inform you on how your perfect bra size should fit.

How Should The Cups Fit

The bra cups should fit comfortably against the whole breast, with no gaps either towards the top or bottom of the breast. If your cup size is too big, you will notice that you have to tighten the bra straps a lot, and this may cause pain or chaff near the armpits. Alternatively, if your cup size is too small, you will experience cup spillage.

How Should The Straps Fit

The straps should fit firmly against your skin without causing pain. The general rule is that you should be able to comfortably fit 2 fingers between your bra strap and your body.

If you have particularly narrow shoulders and you struggle to keep the straps up, try a halter neck bralette or bra style. These straps are attached around the neck rather than the shoulders.

How Should The Band Fit

Did you know that most of your bra support comes from the band? As the elastic in bras actually stretches the more you wear them, you want to find a bra that fits well with the band on the loosest hook. This means that you can then tighten the band as the elastic stretches over time.

How Should The Underwire Fit

The underwire of your bra should sit flat on your torso beneath your breast area, rather than on them. If the underwire is positioned on your breasts, or in between with a small gap underneath, this means that your bra is too small. A bra that’s too small will not provide you with the right support for the weight of your bust, and as a result, the underwire may slip painfully out of place during exercise.

Other Tips To Ensure Your Bra Fits Properly! 

There are some other tips one can try to ensure their new bra fits properly. We know that breasts are as unique as the women that they belong to, so make sure your bra reflects your originality!

For Differently Sized Breasts- Roundup

Using the equation listed below for finding your perfect fit can still be useful even if you have different-sized breasts. When using the equation, it is recommended that you round up your final figure to work out your cup size.

Different Bra Sizes For Different Purposes

Bras are used for different purposes: think sports, loungewear, workwear, and casual wear! Different types of bras and materials will fit differently on your figure whilst offering contrasting levels of support. This is why it’s important to understand ‘sister sizing’ when it comes to bras.

The Equation For Figuring Out Your Bra Size

There is actually an equation that can help you find out your bra size at home! You will first need to measure your band size by using a measuring tape around your torso under your breast area. Take note of this measurement before measuring your cup size. This is a similar process but the difference is that you will need to raise the tape so that it sits in the middle of your breasts.

Once you have both of these measurements, subtract your band measurement from your cup size measurement. This will typically equate to a solo digit number, such as 2. Then, use this number to count what size you are in the alphabet. For example, the number 2 corresponds to the letter B (the second letter in the alphabet), making you a B cup size!

Know Your Size and Your “Sister Size”

Many women can actually wear several different bra ‘sizes’ and this is due to sister sizes! Sister sizes are more or less the same size as your usual fit, but just have slightly different levels of support in certain areas of the bra.


There are many signs that your bra does not fit you correctly, but these have never been properly explained to most women or girls before! Bra fitting seems like it should be straightforward, it can be pretty confusing, especially if you have never been fitted before. With our bra fit tips and advice, you will be able to find your perfect bra size fit. At EBY, we are dedicated to supporting women with our liberating bralettes for women.