A 38H bra means a 38-inch band with a H cup — roughly a 8-inch difference between underbust and bust measurement. Sizes at this end of the chart are less heavily stocked in physical stores, but that's a supply-chain fact, not a comment on how common the size actually is.

A 38H bra means a 38-inch band with a H cup — roughly a 8-inch difference between underbust and bust measurement. Sizes at this end of the chart are less heavily stocked in physical stores, but that’s a supply-chain fact, not a comment on how common the size actually is.

What a 38H Actually Looks Like

A 38-inch band sits snugly around your ribcage just under your bust. Paired with a H cup, that means roughly a 8-inch gap between your underbust and fullest-bust measurement. The straps should need almost no tension to stay up — if you’re constantly retightening them, the band underneath isn’t doing its job.

Sister Sizes for 38H

If 38H isn’t quite right, the two closest sister sizes are 40G (looser band, bigger cup — same volume) and 36I (snugger band, smaller cup — same volume). Every 2-inch band change pairs with exactly one cup-letter change in the opposite direction, because both numbers describe the same underlying volume.

38H in Other Sizing Systems

SystemBandCup
United States38″H
United Kingdom38″FF
Europe (FR/ES/BE)115cmH
Italy115cmI
Japan/Korea95cmH

Fit Tips at This Size

Check the center gore first — if it doesn’t sit flat against your sternum, the cup is too small even if the band feels right. Full-coverage and plunge styles with molded or seamed cups tend to hold shape better at this volume than soft, unlined styles.

Want your exact size instead of an estimate? Use the Main Bra Calculator — free, private, takes under a minute.

Common Mistakes at 38H

Assuming a band that felt fine in the store will still feel fine after a full day — bands relax slightly with wear, so what feels perfect at 9am can feel loose by evening.

Where to Actually Find This Size

Mainstream retailers tend to stock the middle of the size range most heavily, so this specific combination is more reliably found through specialty or extended-size sellers online.

A Common Myth Worth Clearing Up

People sometimes assume a bigger cup letter automatically means less comfort or more visible bulk under clothing — construction and band fit affect both far more than the letter itself.

Why the Same Size Fits Differently Across Brands

Seam placement inside the cup changes how volume actually sits — a seamed cup with more panels can mold to an individual shape more precisely than a single molded cup, which matters more at some sizes than others.

Making a 38H Last

A band that’s lost its stretch (feels loose even on the tightest hook) is a genuine sign to replace it, not a sign you need a smaller size — the size hasn’t changed, the elastic has.

Style Recommendations for 38H

Full-coverage and plunge styles with real structure hold up better than soft, unlined designs at this range.

Why This Number Isn’t Permanent

Weight fluctuation of even a few pounds can nudge a band size, especially at the boundary between two sizes — this isn’t a flaw in the measuring process, just how bodies naturally vary.

Shopping Online at This Size

Reading recent reviews that mention true-to-size feedback for the exact style (not just the brand generally) is one of the more reliable ways to predict fit before buying online.

FAQ

Does this size run the same across every brand?+

No — cut, fabric stretch, and construction vary enough that the same label can fit differently by half a size or more between brands.

Can I convert this to international sizing?+

Yes — see the conversion table below for UK, EU, Italy, and Japan/Korea equivalents.

Is this size hard to find in stores?+

It depends on the retailer — mainstream chains often carry a narrower range, while specialty and extended-size retailers stock this range more consistently.

Does this size run the same across every brand?+

No — cut, fabric stretch, and construction vary enough that the same label can fit differently by half a size or more between brands.

Should I expect this size to change over time?+

Yes, for most people — weight change, age, hormonal shifts, and even different laundry habits can all move the number gradually, which is why periodic re-measuring matters more than getting it right once.

Is there a best time of day to check this?+

Mid-morning to early afternoon tends to be most representative for most people — very early morning or late evening can show minor temporary swelling that isn't your typical baseline.

Does posture affect the measurement?+

Yes — measuring while slouching or with unnatural posture can shift the numbers slightly; stand naturally with normal, relaxed posture for the most accurate result.

Claire Bennett
Claire Bennett
Bra Fit Educator & Founder, Bra Size Calculator

Claire spent 10+ years hand-fitting women in specialty lingerie boutiques before building this site. She writes from real fitting-room experience — not a clinical or medical background — and every calculator here reflects the same measure-first approach she used in-store.