How Should A Bra Fit? (How to Tell If It's Too Big)

Posted by Alexis Canary on

How Should A Bra Fit? (How to Tell If It's Too Big)

Ladies, your bra matters. Just because it’s an undergarment doesn’t mean you should underestimate how important it is. Not only does it affect how your blouses and t-shirts hang on your body, but also how you feel—and that takes precedence above all else. 

Too tight? You have perpetual marks from suffocating straps and brutal bands. Too loose? You feel your breasts moving, shifting, and even bouncing around as you try to go about your day.

Just right? Let’s talk about what that looks and feels like—and how you can enjoy it for yourself. 

How is a Bra Supposed to Fit?

With so many ill-fitting bras out in the marketplace, it’s a shame that no one ever taught us how to know if a bra fits. That’s exactly why we’re here today. 

To that end, there are three main components to any bra and, subsequently, to finding the right fit for you—the band, the straps, and the cups. The problem could lie in any of the three individual dimensions, or it could be a combination of issues.

First, let’s pinpoint the problem area. Then, we can work towards fixing it.

First Potential Problem: The Band

Your bra band should be doing most of the supporting work, almost as though you were wearing a strapless bra. The straps ensure a close fit but should not be doing the heavy lifting. 

In which case, you need to check the back of the bra in a mirror. The bottom of the band should sit almost perfectly horizontal across your back. If it’s being pulled up—like the slight peak of a mountain—you’ve probably tightened your straps too much. 

As a petite woman, this may have been a necessary adjustment to ensure a better fit in the bra sizes you currently own. We get it—a girl’s gotta do what a girl’s gotta do! But this shouldn’t be the case if the band, straps, and cups all fit you properly. 

Signs that your bra band is too big:

  • If you slip the straps off your shoulders and your bra immediately falls or slides down
  • If you can pull the band several inches away from your back with no problem
  • If your breasts don’t feel adequately supported
  • If the straps are digging into your shoulders trying to hold up your breasts
  • If you’ve tightened your straps too much to compensate for a loose band

If you’ve adjusted your hook and eye to the smallest possible level and these problems persist, it’s probably time to downsize your bra band. But it’s not as simple as downsizing from, let’s say, a 32AA to a 30AA. The band would likely fit but the cups would feel too small, even though they’d both be marked as AA. That’s because cup sizes refer to the difference between your rib cage (the band) and your breasts (the cups), not your absolute breast size.

This is where sisters—nope, not the twins (wink, wink)—come into play. We’re talking about sister sizes, that is. 

All bra sizes have sisters.

Much like the variations in real siblings, the bra dimensions across sister sizes are completely different but as a whole, they function very much the same. If you increase the cup size and decrease the band length proportionally, the overall cup volume is consistent but the bra may fit you better by addressing your specific needs.

For petite women, get to know your sisters with this size chart:

I currently wear a… and the band is too big!

I should try a… 

for a better fit!























The trend follows as you get into the larger sizes, too. The opposite applies if your band is too tight and you’re in need of a little more breathing room!

Second Potential Problem: The Straps

If the band is the hero of our breast-supporting story, then the straps are the sidekicks. They maintain a snug fit by pulling the top of the bra closer against the body (but they should only provide a fraction of the actual support). 

Knowing how to tell if a bra fits isn’t rocket science but it also doesn’t come naturally. So many of us have been wearing the same (incorrect) size for so long that we hardly even recognize there’s a different way to feel. 

Signs that your bra straps are too big:

  • If they regularly slip off your shoulders 
  • If you can easily fit more than a few fingers between your strap and your shoulder
  • If you can lift the straps a half-inch or more away from your body

More often than not, women adjust their bra straps to be too tight, not too loose, as a way of compensating for an otherwise ill-fitting bra.

If your straps are too loose, you’ll probably be the first one to know!

If tightening them all the way doesn’t remedy your strap-slip situation, this could also be a sign that you have narrow or sloping shoulders and might benefit from a halter or racerback bra design. Otherwise, a quick needle and thread adjustment can often do the trick! 

Third Potential Problem: The Cups

When it comes to bra sizes, there’s no difference between half-empty and half-full. The problem can’t be fixed with a shift in perspective. 

The only solution is actually filling out your bra cups—all the way to the brim. 

So, how should a bra cup fit? Your breasts should perfectly fill out your cups, with no gaping or wiggle room and no overflow or uncomfortable compression. 

Signs that your bra cups are too big:

  • If there’s a gap between the top of the cup and your breast
  • If you remove your padded bra and notice wrinkles in the padding
  • If you don’t feel fully supported or are constantly readjusting your bra
  • If you’ve tightened your straps too much to compensate for a gaping cup

Just like with an oversized bra band, many petite women simply tighten their bra straps as far as they’ll go to compensate for ill-fitting bras. 

But it doesn’t have to be this way. 

Even the smallest breasts deserve to sit perfectly in their bra cup for absolute comfort. When downsizing your bra cups, be sure to adjust your band length accordingly by finding your sister size. After all, a well-fitted cup isn’t worth much if your band is now pinching your skin.

How Should a Bra Fit? Just Like Lulalu’s

Far too many people believe that petite women have it easy when it comes to bra shopping. While we may have different struggles than women shopping for DD sizes and beyond, that doesn’t mean that the perfect petite bras are always readily available.

That’s where we come in. Lulalu was created to be that go-to source of support—literally and figuratively—for A, AA, and AAA breasts. 

All you have to do is find your perfect fit with us, first by answering a few simple questions, then by shopping from our tailored line of bras in a variety of sizes, cuts, designs, and fabrics made for real bodies. 

“Small” isn’t the same across every petite woman. 

Neither are our bras. 


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