By Bra Fit Educator Claire Bennett
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Bra Fitting Guide

38H Bra Size Guide

38H bra size explained: measurements, sister sizes, international equivalents, and fit tips.

By Claire Bennett
3 min read • Updated Nov 2026
Direct Fit Answer

A 38H bra means a 38-inch band with an H cup, or 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.

38H bra size chart showing 37" to 38" underbust, 46" bust, 1810 cc cup volume, and sister sizes
Size 38H Chart
US 38H fits a 37" to 38" snug ribcage and 46" full bust (~1810 cc per cup), matching UK 38FF and EU 85H.Bra-SizeCalculator.com Guide
Size 38H Quick Reference

38H Measurements, Cup Volume & Global Sizes

Verify My Size
Snug Underbust Ribcage37" – 38"94–97 cm ribcage
Fullest Bust Perimeter~46"+8" over band (117 cm)
Single-Cup Volume~1810 ccPair tissue ~7.6 lbs (3439 g)
Bralette & Lounge ScaleXL-Busty / 1X-CurvyAlpha wireless equivalent
Snugger Band Sister36I
View 36I →
Target Size38H (~1810 cc)
Baseline
Roomier Band Sister40G
View 40G →
38H Across 7 Global Lingerie Tag Standards
US38H
UK38FF
EU85H
AU16FF
FR100H
IT5H
JPH85
Size 38H Picks

Bras That Fit Well in Size 38H on Amazon

Picked for steady 38-band support and true H-cup depth, with no paid brand placements.

Search All 38H on Amazon
Rosewood two-part seamed floral lace full-figure underwire bra with tall center gore and wide strapsTop Pick for Large Bust$44 – $68
Wacoal4.6

Wacoal Women's Retro Chic Full-Figure Underwire Bra

Full Bust Lift & Forward Projection (C–H)

Structured berry high-impact camisole sports bra diagram showing upper mesh bounce panel and wide strapsEditor's Choice$36 – $56
Glamorise4.5

Glamorise Women's No-Bounce Camisole High-Impact Sports Bra

Running, HIIT & High-Impact Bounce Control

Champagne ivory strapless bandeau underwire bra diagram showing molded lace cups and silicone grip wingsEditor's Choice$46 – $68
Wacoal4.5

Wacoal Women's Red Carpet & Halo Lace Convertible Strapless Bra

Non-Slip Strapless Grip Up to G/H Cup

What a 38H Actually Looks Like

A 38-inch band sits snugly around your ribcage just under your bust. Paired with an 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 (rather than the brand generally) is one of the more reliable ways to predict fit before buying online.

Frequently Asked Questions

No. Cut, fabric stretch, and construction vary enough that the same label can fit differently by half a size or more between brands.
About the FitterChecked Across 7 Sizing Systems
Updated: November 2026
Written & Reviewed ByClaire Bennett• Bra Fit Educator & Founder

Claire Bennett spent over 10 years fitting women in specialty lingerie shops before starting Bra-SizeCalculator.com. She isn't a doctor, and she doesn't make up fake credentials. She shows the exact tape math behind every result so you can shop without guesswork.

10+ Years In-Store Boutique Fitting7 Global Sizing Systems CheckedUnsponsored Fit GuidesHow Our Sizing Works