How to Fix an Overflowing Bra

Illustration of women wearing bras that are too small.

Spillage & overflow are common bra issues, especially for those wearing a size that’s too small. Aside from sizing, there are several other potential causes for why your bra isn’t fitting right.

Lucky for you, ThirdLove aims to help everyone find their ideal bra, no matter the size or shape of their breasts. Learn how to fix and prevent bra spillage and find your perfect bra size.

How Do You Fix Side Boob Spillage?

Bra spillage often happens to breasts that are fuller at the sides. There are several options to consider if you want to reduce side boob spillage.

Ensure Your Cup and Band Size Are Correct

About 80% of women wear the wrong bra size, and this results in common bra fit issues such as bra spillage, cup gaping, breast pain, and more. Wearing the correct bra size is crucial to ensure adequate support and comfort.

At ThirdLove, we offer an online Fitting Room Quiz to help you find your perfect size in the comfort of your own home. If you would rather measure your bra size with a tape measure, there are two measurements to consider: your cup size and your band size. Follow these instructions to measure each, the ThirdLove way:

Band Size
Wearing a non-padded bra, use a soft tape measure to get your band measurement. Find this by wrapping the tape measure around your ribcage, just underneath where your bra band rests. If the measurement is an even number, add two to it; if the measurement is an odd number, add three to it. The sum is your correct band size, and these additional couple of inches that we added makes up for the size difference between when the elastic in the bra band is stretched or relaxed. For example, if your ribcage measurement is 32 inches, then your band size is 34. If the measurement is 35 inches, then your band size is 38.

Cup Size
The first step to measuring your cup size is to get the measurement from the fullest part of your breasts (usually where the nipple is). To do this, stand with your arms resting at your sides and pull the tape measure around so that it feels snug but not very tight. Note what the number of inches is, and then subtract your band size from that number. The number you end up with determines your cup size.

  • 0 = AA cup
  • 1 = A cup
  • 2 = B cup
  • 3 = C cup
  • 4 = D cup
  • and so forth…

You might find that the difference falls somewhere in between. Traditionally, you would have had to settle for a bit tighter or looser of a cup, but not anymore! ThirdLove aims to help everyone find the perfect fitting bra, which is why we also provide half cup sizes. So if your difference is 3½ inches, our C½ cup will be your perfect fit.

Wear Your Ideal Bra Style

There are many different bra styles available, and each style tends to support and flatter different breast shapes. Understanding your breast shape will allow you to make more informed bra purchases.

Change How You Wear Your Bra

How you wear your bra makes a huge difference in fit and comfort. When putting on your bra, scoop each breast into its respective cup and make sure the nipple rests at the center of the cup. This method of putting a bra on ensures the best possible fit every time.

Consider Wearing a Wire-Free Bra

Wire-free bras are generally more flexible than traditional wired bras, making their sizing more flexible as well. If you’re fluctuating between sizes, or have yet to find your perfect traditional bra size, it is typically easier to buy a wireless bra that fits.

While it’s easier to find a flexible fit with wireless bras, they can also be less supportive, especially for those with larger cup sizes, because they are only offered in a handful of alpha sizes. Our 24/7® Classic Wireless Bra puts all this behind. With innovative Precise Sizing™ which offers + and ++ sizes to support small band and big cup combinations, this wireless bra offers three times more sizes than typical wireless bras for a custom fit. If you’re looking for a wireless bra that actually supports, this is a great option.

Try Out a Full Coverage Bra

A full coverage bra is designed to cover the entire breast, helping to avoid spills and providing more overall support. Those with larger breast sizes tend to prefer this bra style over others, as it offers additional comfort and helps reduce back, shoulder, or neck strain from lack of support. This design is especially useful for preventing spillage from the top of the cups as it offers more coverage on average. ThirdLove's ComfortStretch Smoothing Full Coverage Bra is a great full coverage bra with armhole and back smoothing. It's 4-way stretch fabric will provide a body-hugging fit and keep your girls in place while staying soft and comfortable.

ComfortStretch Smoothing Full Coverage Bra


ComfortStretch Smoothing Full Coverage Bra



Illustration of a woman wearing a bra that is too small.


How Do You Know if Your Bra Is Too Small?

If you’re experiencing bra overflow, you may be wondering whether your bra is too small. There are several signs of a too-small bra that you should watch out for:

  • A squeezing feeling in your chest
  • Bra straps that dig into your skin
  • Breast spillage out the top, bottom, or sides of the bra
  • Gapping at the front center of the band
  • Increased acid reflux
  • Irritated or chafing skin
  • Lack of breast support
  • The need to make constant adjustments
  • Underwire that digs into your skin or causes irritation
  • Upper body pain, especially in the neck, shoulders, and back

If you notice any of these issues, consider remeasuring your cup and band sizes. Wearing a bra that’s too small can hinder your comfort, health, and posture, so size up if you need to.


Illustration of a woman wearing a bra that is too big.


How Do You Know if Your Bra Cup Is Too Big?

If your bra cup is too big, it’s not offering you the support or comfort you need. Next time you wear your bra, check to see if you notice any of these common bra fit issues:

  • A band that rides up
  • Breasts not filling the cups
  • Cups that wrinkle
  • Lack of breast support
  • Loose band or straps
  • Excessive breast movement
  • Straps slipping down the shoulders
  • The need to make constant adjustments
  • Upper body pain, especially in the shoulders

If you notice any of these signs, consider going down a cup size and see how the bra fits. In case going down a full size is too much for you, ThirdLove also offers bras in half sizes. 

How to Avoid Bra Spillage

Bra spillage is a problem affecting many women, but there are steps you can take to avoid this common issue:

  • Measure your breasts before buying a new bra
  • Wear the correct bra size for your breasts
  • Choose bra styles and cup shapes best suited for your breasts
  • Consider wearing side-support bras

For more troubleshooting, check out our helpful resources on bra styles and common bra fit issues. If you would like a simple way to find your perfect bra size and style, take our online Fitting Room Quiz! The more you know about your unique breasts and bra options, the closer you are to finding your ideal bra.