Bra Fit Checklist: How To Find A Bra That Fits Perfectly

Model wearing black t-shirt bra

A well-fitted bra is more than just a luxury: it’s a necessity. Imagine the relief of stepping into a day knowing that your bra isn’t going to betray you with pinching straps, a band that rides up, or cups that leave you gaping or overflowing. More than the aesthetics, finding the perfect fitting bra gives you comfort, support, and confidence. A well-fitting bra can boost your posture, improve your mood, and even help to reduce back pain. Yet, studies show that many women wear the wrong size bra. 

We all know the frustration of dealing with an uncomfortable bra. This guide will equip you with the knowledge to find a bra that fits you perfectly so you can feel your best throughout the day.


Bra Fit Checklist

The key to bra fitting success lies in focusing on four key areas: the band, the cups, the underwire (if applicable), and the straps. Let’s break it down for you.

  • The Band

The band is the foundation of your bra’s support. Where should a bra sit on your back? The band should ideally sit snug but comfortable around your torso, directly under your bust. If it’s riding up, it’s too loose, and a size down is in order. Conversely, if it’s leaving red marks or squeezing the air out of you, go up a size.

  • The Cups

Cups are the carriers of comfort. Here’s what to check. Ask yourself, “Does my bra fit right?” The cups should fully cradle your breasts without any overflow or spillage. On the other hand, they shouldn’t gape or leave space at the top. They should hug your curves nicely, creating a smooth silhouette under your clothes. Remember, a well-fitted cup ensures that your bra isn’t just supportive; it’s equally flattering.

  • The Underwire

If your bra has an underwire, it should sit flat against your rib cage and follow the natural curve of your breast. It should not poke or dig into the underside of your breast. The underwire is there to provide additional support, especially for larger busts. If it’s sitting on your breast tissue or causing discomfort, you might need to adjust or try a different style.

  • The Straps

Straps should sit comfortably on your shoulders without digging in or slipping off. They’re there to keep your bra in place, but they shouldn’t be doing all the heavy lifting.

So, how should a bra fit? It’s all about balance and finding what works best for your body. By checking these components, you can ensure your bra fits well.


How Should Your Bra Fit?

So, how should a bra fit? A bra that fits is comfortable and supportive. There should be no gaps in the cups, no digging in of the band, and the straps should not fall off or be too tight. Sounds pretty simple, right? Well, there’s more to finding a bra that fits perfectly than that. Read on as we cover how each bra section should fit and how you can find your perfect size.


How the Cups Should Fit

Take a look at where the tops of your cups and your body meet. The cups should form to the curve of your breasts without gaping or causing them to spill over.


Short haired woman wearing ThirdLove's Classic T-shirt Bra in Black
ThirdLove’s 24/7 Classic T-Shirt Bra features memory foam cups that contour to your breast tissue.


  • If your cups gape: The room between the cup and the top of your breast can mess with a sleek silhouette. First, try tightening the straps. You may need a smaller cup size if that doesn’t fix the problem. Our half-cup sizes can often do the trick.
  • If you have cup overflow: If your cups runneth over, it’s time for a larger cup size. That way, you’ll stay supported without being squeezed. Our full coverage styles can also help, as its cups rise higher on your breast, reducing “spillage.”
  • If you have side overflow: Similar to cup overflow, the culprit is often too-small cups. Go up a full or half-cup size — that should do the trick. If not, try a smaller band.


How the Straps Should Fit

Your straps should sit snugly on your shoulders without digging in or leaving indentations on your skin.


Short haired woman reaching over her shoulder to make sure bra straps fit.
Pleated, halfway adjustable straps make our Classic T-Shirt Bra comfortable on the shoulders and prevent it from slipping off them.


  • If your straps slip: If you're constantly hoisting them back onto your shoulders, it’s probably time to tighten them. The elastic can stretch out as you wear your bra, and it’s easy to forget to adjust them as you go. If slipping persists, it could be time for a new style. Try one with narrower-set straps, like t-shirt bras or full-coverage bras, to help keep them on your shoulders.
  • If your straps dig in: If your shoulders are bearing the weight of your breasts, your bra isn’t fitting correctly. Try a smaller band size since your band (not your straps!) should support you. (We’ve even designed some of our bras, like our Perfect Coverage, to have additional padding on the straps to help keep them in place comfortably.)


How the Band Should Fit

When wearing a new bra, be sure to start on the loosest hook. You can tighten it as the band naturally stretches over time. The band should feel comfortably snug around your body without constricting, and it should definitely not feel as though your band is digging in.


Woman reaching behind to check if the band of her ThirdLove Classic T-shirt Bra fits.
With three sets of hook-and-eye closures, you can tighten your bra over time. With a new bra, the band should fit snug and comfortably on the loosest set of hooks.


  • If the underwire sits on your breasts: Also known as slipping out the bottom, this fit issue is one of the more annoying ones. Try a smaller band size so it fits more snugly. Be sure to test the new band on the loosest hook: it should fit snugly, and you can tighten it over time.
  • If your band rides up: If your band is sitting high on your back, it means it’s too loose. Go down a band size or adjust your hook and eye to a tighter closure. However, if you’re experiencing this issue with a new bra, it may be because you’re wearing a band size too big.


How to Measure for a Bra that Fits

Now that you know how to check that your bra fits, you might wonder how to measure for your perfect size. Your bra size is based on your band size (number) and cup (letter), and this is typically calculated based on your measurements around your rib cage and your bust. One factor that’s often overlooked is your breast shape, as it plays a large factor in your size and what type of bra will support you the best. To learn more about calculating your bra size at home with a tape measure, explore our guide to measuring your bra size. Don’t have a tape measure at home or want some help? Take our online Fitting Room Quiz to find your perfect size and fit in just a few minutes!


How To Shop For a Bra That Fits

When it comes to shopping for bras, you can either shop in person or online. Purchasing bras in person comes with the benefit of trying on the bra and ensuring it fits before buying it. Unfortunately, most retail stores don’t carry as wide of a variety of styles and sizes as their online counterparts, so you might not have as many options. On the other hand, online stores typically offer an extensive range of bra styles, shapes, and sizes, so you can find one in a silhouette and size that suits you perfectly. Most online stores do come with the huge downside that because you can’t try the item on in person, it’s more difficult to size yourself, and you could potentially end up with an ill-fitting bra. Because you can’t try the item on when online shopping, we recommend reading through many reviews to better understand sizing and support.

Thankfully, ThirdLove offers a wide range of sizes and styles in our retail stores and online. In stores, our helpful bra experts can help you find the perfect fit and place orders for any bras for you if they don’t have it in store. Online, we have a streamlined Fitting Room Quiz that will help you find your perfect size easily, and if you need more help, our online bra experts are just one click away. If you receive your bra and aren’t happy with the fit, we offer a generous 60-day return to ensure you find your perfect bra fit!

Half the reason we get out of bed in the morning is to troubleshoot fit issues, so check out our full guide to fit issues. If you still need help, feel free to chat with our experts for help!


Choosing ThirdLove for All Your Bra Needs 

Choosing the perfect bra isn’t just about finding a pretty design; it’s about finding one that understands your needs. In the vast and often daunting world of bra shopping, ThirdLove stands out as a beacon of hope and a champion of perfect fit. With our wide range of sizes and styles, every woman can rest assured of a bra that caters to her unique needs and preferences. From the memory foam cups that contour to your curves to the adjustable straps that provide customized comfort, ThirdLove’s offerings are a true testament to our commitment to empowering women.

But what truly sets ThirdLove apart is our unwavering dedication to helping you find your perfect fit. Take advantage of our available tools to ensure you get your perfect fit. Whether it’s our online Fitting Room or the generous return policy, explore and experiment until you find that bra that is yours. So the next time you are out bra shopping, don’t settle for anything that doesn’t check all the boxes on the checklist.