Understanding a 38C Bra Size

You've heard the numbers and letters your whole life, but what does "38C" actually tell you about your bra size? Knowing these measurements transforms bra shopping from guesswork into confidence. Here's what 38C bra size means and how to measure yourself accurately.

What Does 38C Actually Mean?

A 38C bra size consists of two measurements that work together to create your unique fit. The number "38" represents your band size, or the measurement around your ribcage just below your breasts. The letter "C" indicates your cup size, which is determined by the difference between your bust measurement and your band measurement.

For a 38C, this means your bust measurement is about 3 inches larger than your band measurement. The "C" cup indicates this 3-inch difference.

Many women wear 38C. It's considered a common size that bridges the gap between what some retailers call "standard" and "full figure" sizing. Knowing these measurements helps you shop more confidently and recognize when a bra truly fits well.

How to Measure for a 38C Bra

Getting Your Band Measurement

Start by wrapping a soft measuring tape around your ribcage, directly under your breasts. Keep the tape parallel to the floor and snug against your body. You should be able to slide one finger underneath.

Finding Your Bust Measurement

Next, measure around the fullest part of your chest, keeping the tape level across your back. The tape should rest comfortably over your breasts without squeezing.

Calculate Your Bra Size

Enter your band and bust measurements into our bra size calculator for an instant and accurate bra size calculation.

Tips for Accurate Measuring

For the most accurate results, measure yourself every 6-12 months to keep up with natural body changes and fluctuations. Wear your best-fitting unpadded bra when measuring. 

Sister Sizes and When to Use Them

Sister sizes are bra sizes that hold the same volume in the cups but have different band sizes. For 38C, your sister sizes are 36D (smaller band, larger cup) and 40B (larger band, smaller cup).

These alternatives can be helpful when a specific style runs large or small in the band, you're between sizes, you prefer a tighter or looser band fit, or a particular brand's sizing doesn't align with your usual size.

Keep in mind that while sister sizes maintain cup volume, they distribute that volume differently. A 36D will feel snugger around your ribcage, while a 40B offers more band room but might not provide the same level of support.

Common Fit Issues and Solutions

Band Problems

If your band rides up in the back, it's too loose. If the fit is only slightly off, try your sister size 36D for better support. A band that feels restrictive or leaves deep marks needs to be larger; consider trying 40B or staying with 38C but looking for brands with stretchier bands.

The band should sit horizontally around your body and provide 80% of your support.

Cup Concerns

Spillage over the top or sides means you need more cup coverage. While 38C might be your measured size, you might prefer 38D in certain styles, especially if you have fuller upper breast tissue.

Gapping or wrinkling in the cups could mean the style doesn't suit your breast shape rather than being the wrong size. Different bra styles distribute breast tissue differently.

Comfort Adjustments

Start new bras on the loosest hook to allow room as the elastic relaxes over time. Adjust your straps every few wears so they stay in place without digging in.

If you're constantly readjusting, the band might not be providing enough support. Consider styles with wider bands or side panels for additional stability.

Finding Your Best 38C Bra Styles

Your lifestyle and preferences matter as much as your measurements when selecting bras. For everyday wear, wire-free options with structured support can provide comfort without sacrificing shape. Look for features like wide bands, side slings, or molded cups that offer support through design rather than underwire. The CrossOver Bra is an excellent choice for a 38C bra size.

Shop CrossOver Bra

For work or special occasions, consider styles with smooth, seamless cups that disappear under clothing; convertible straps for versatility with different necklines; full-coverage cups if you prefer more security; or plunge styles if you wear lower necklines. The CloudEmbrace Bra, a modern wireless t-shirt bra with moderate cup coverage, is a great option.

Shop CloudEmbrace Bra

Athletic activities call for compression or encapsulation sports bras designed for your cup size. Many brands now make sports bras specifically for C+ cups that provide both support and comfort during movement. For light activity, try the CrossFlex Activity Bra.

Shop CrossFlex Activity Bra

Bra fitting is personal. What works perfectly for another person wearing 38C might not suit your body shape or preferences. Take time to try different styles and brands to find what makes you feel most comfortable and supported throughout your day.