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34H Bras

(40 products)

How a 34H should fit

A 34H is a full-bust size, and the engineering matters more than the label. Wide side wings, a firm band with four hooks and seamed cups will outperform a prettier bra with thin straps every time.

Sister sizes to try

  • Band loose, cup fine — try 32HH
  • Cup overflowing — try 34HH
  • Band digs in — try 36GG
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The HauteFlair Edit · Updated 2026

34H Bras: What a UK 34H Cup Is, and Why It's a US 34K

A 34H isn't one size — it's one size written in two alphabets. The band is a 34 in every system. The cup is where they split: most full-bust brands label the H the UK way, where H sits high on the ladder and equals a US K.

Below: exactly what 34H converts to across US, UK and EU, why a US 34H is actually a smaller cup, how to measure to be sure, your sister sizes, and the styles built to hold an H cup all day.

Quick Answer

What is a 34H bra size?

A 34H bra has a 34-inch underband and an H cup — but the cup depends on the sizing system. In UK sizing, which most full-bust brands use, 34H is a true H cup: it equals a US 34K and an EU 75K, and describes a bust roughly 11 inches larger than the band. The catch that trips shoppers up: a US 34H is a different, smaller cup — it lines up with a UK 34FF, three steps down the ladder. So if you wear a UK 34H, reach for a US 34K, not a US 34H. Sister sizes, holding the same cup volume, are 32HH and 36GG (32L and 36J in US letters). Shop 34H bras in t-shirt, strapless, sports and full-figure styles.

UK H = US KThe letter jumps three notches
Band 34, cup H34 inches around the ribcage
≈ 11 inchesBust minus band at this cup
A US 34H is smallerThat's a UK 34FF, not this
Shop by style
All 34H Bras T-Shirt Bras Strapless Sports Bras Full Figure Minimizer All Bras

How to choose a bra at 34H

A full H cup asks more of a bra than a smaller size does. Five things decide whether it holds all day or gives up by noon.

What to check What good looks like Why it matters
Band fit Level all the way around, snug on the loosest hook, two fingers under it and no more At an H cup the band carries almost all the support — a band that rides up throws the entire load onto your shoulders
Cup construction Three- or four-part seamed cups, or moulded cups with a side support panel and a sling Seams and slings project a full cup forward and contain it; an unseamed stretch cup collapses at this volume
Underwire Tall, wide wires that encircle the whole breast and sit flat on the ribcage without poking the underarm A short or narrow wire rides up onto breast tissue — that's a fit fault at an H cup, not a comfort quirk
Straps Wide, cushioned, set closer to the neck, fully adjustable, ideally with a leotard or U back Thin straps at a full cup dig grooves into the shoulder; width spreads the load the band leaves behind
Gore & wings Centre gore flat to the breastbone; tall side wings (three or four hooks) A floating gore means the cup is too small; tall wings stop side spillage and anchor the band

34H in US, UK, EU and beyond

The same body, seven labels. This is where cross-system shopping goes wrong — the band never changes, the cup letter always does.

System Size How it's written
UK 34H The size on this page — used by most full-bust brands
US 34K US stacks D's then runs the alphabet, so H lands at K
EU 75K Band in centimetres; US 34 = EU 75
France / Spain 90K EU band plus 15 — same body, bigger number
Italy 2K Italy numbers bands 1–6; EU 75 = Italian 2
Australia / NZ 12H Numeric band (US 34 = AU 12), UK-style cup letter
Japan 75K EU band; Japanese cups run small, so size up one cup

So is a UK 34H the same as a US 34H? No — and this is the single most common 34H mistake. The letter "H" means about 8 inches of bust-to-band in US sizing and about 11 inches in UK sizing, a three-cup gap. A US 34H is a UK 34FF; the UK 34H on this page is a US 34K. If a brand's chart looks two or three letters off from what you expect, that's the US–UK split, not an error. Treat every conversion as the size to try first, then check the brand's own chart — see our full bra size conversion guide.

Find your 34H bra

Pick the card that matches what you need it for — then tap through to shop.

01

Everyday, under everything

A moulded t-shirt bra with a side sling: smooth under knit, structured where an H cup needs it.

Shop t-shirt bras →
02

Full coverage all day

Seamed cups, wide straps, tall wings, a firm band. The workhorse category at an H cup.

Shop full figure →
03

Running, lifting, moving

Encapsulation, not compression. Separate structured cups beat a squash-it-flat crop at 34H.

Shop sports bras →
04

Strapless that stays

At an H cup, strapless lives or dies on the band. Look for longline cuts and silicone grip.

Shop strapless →
05

Smooth the line

A minimizer redistributes rather than flattens — a cleaner profile under a blouse without losing support.

Shop minimizers →
06

Not sure it's your size?

If your current 34H gapes or the gore floats, the conversion or your measurements may be off. Start here.

Convert my size →

The band does the lifting; the straps only steady it. Get an H cup fitted to that rule and the grooves, the ride-up and the four-o'clock ache mostly disappear.

The HauteFlair Standard

The complete 34H sizing guide

Measuring, the US–UK gap, sister sizes, the fit tells and the vocabulary.

01How to measure for a 34H at home+

Two measurements, taken in a soft unpadded bra or none at all, tape level:

  • Band: snug around the ribcage directly under the bust. A 34 band comes from an underbust near 33–35 inches.
  • Bust: around the fullest point, tape parallel to the floor, not pulled tight.
  • Cup: subtract band from bust. An 11-inch difference is a UK H (US K); 10 inches is a UK GG, 12 a UK HH.

The result is a starting size, not a verdict. Cut varies mill to mill, so let the fit checks below decide — and if you're on the line between letters, try the size plus its sister sizes.

02US 34H vs UK 34H: the three-cup gap+

The same letter means two different cups, because the two systems count differently above D:

  • UK ladder: D, DD, E, F, FF, G, GG, H — single letters with doubles. UK H sits at about 11 inches.
  • US ladder: D, DD, DDD, then G, H, I, J, K — stacked D's, then straight alphabet. US H sits at about 8 inches.
  • The result: a UK 34H is a US 34K; a US 34H is a UK 34FF. Three cup letters apart, same word.

Most full-bust labels (Panache, Freya, Fantasie and the like) are UK-sized, which is the H on this page. If you've been buying US-labelled bras, don't assume the letter carries over.

03Sister sizes: 32HH, 34H, 36GG+

Cup volume moves with the band, so 34H has neighbours holding roughly the same cup:

  • Down a band, up a cup: 32HH (32L in US letters) — for a firmer band that feels tighter.
  • Up a band, down a cup: 36GG (36J in US letters) — for a looser band with the same cup room.

Reach for a sister size when the cup fits but the band doesn't, or when your exact size is out of stock in a style you want. What you should never do is loosen the band to fix the cup — that hands the support to your shoulders. The full logic is in our sister sizes guide.

04The five fit tells at an H cup+

Stand at a mirror. In order of usefulness:

  • Band riding up at the back — band too loose. Go down a band, up a cup (your sister size).
  • Gore floating off the breastbone — cup too small, or the wire is too narrow for you.
  • Spillage at the top, underarm or under the wire — cup too small. Not a shape problem.
  • Wrinkling or gaping at the top of the cup — cup too big, or the wrong style for your shape.
  • Straps digging deep grooves — you've tightened them to cover for a loose band. Fix the band first.

Check on the loosest hook when the bra is new; you move to the tighter hooks as the elastic relaxes over time.

0534H, UK H, US K: the vocabulary+
  • 34H — a 34 band with a UK H cup, the convention most full-bust brands print.
  • US 34K — the same body in US letters, because US sizing runs further up the alphabet.
  • EU 75K — the same body again; 75 is the band in centimetres, not the bust.
  • Full bust vs plus size — 34H is a full-bust size (a large cup on a mid band), which is built differently from a plus-size bra (a larger band).
  • Sister size — a different band-and-cup pairing holding the same cup volume; 34H's are 32HH and 36GG.

34H bras FAQ

The questions shoppers ask most, answered straight.

What is a 34H bra size?

A 34H has a 34-inch underband and an H cup. In UK sizing — used by most full-bust brands — that's a bust about 11 inches larger than the band, equal to a US 34K and an EU 75K. It's a full-bust size: a large cup on a mid-size band.

Is 34H a UK or US size?

Almost always UK. Most brands that make an H cup — Panache, Freya, Fantasie and similar full-bust labels — use UK sizing, where the ladder runs D, DD, E, F, FF, G, GG, H. US sizing rarely uses a plain H at a 34 band the same way, so a 34H you see in stock is generally a UK 34H.

What is a 34H in US sizing?

A UK 34H is a US 34K. US sizing stacks D's (DD, DDD) and then runs the alphabet G, H, I, J, K, so the UK's single-letter H lands three notches further along at K. The band stays a 34 in both systems — only the cup letter changes.

Is a 34H the same as a 34K?

Yes, across systems: a UK 34H and a US 34K describe the same cup volume on the same band. If you've been fitted in one system and are shopping a brand that uses the other, this is the pair to remember.

What is a US 34H in UK sizing?

A US 34H is a UK 34FF — a smaller cup than the UK 34H on this page, by three letters. This is the trap in H-cup shopping: the same letter sits at about 8 inches of bust-to-band in the US and about 11 inches in the UK. Always check which system a brand uses.

Is 34H a big bra size?

It's a full-bust size, larger than average, but the letter alone doesn't tell the whole story. Cup volume is measured against the band, so a 34H holds more than a 32H (smaller band) and less than a 36H (larger band) even though all three read "H". The band is half the size.

What are the sister sizes for 34H?

32HH and 36GG — the same cup volume on a different band. Drop to 32HH for a firmer band, move up to 36GG for a looser one. Use a sister size when the cup fits but the band doesn't, or when your size is sold out in the style you want.

How do I measure for a 34H at home?

Measure snugly around your ribcage under the bust for the band, then around the fullest point with the tape level. Subtract the first from the second: an 11-inch difference on a 34 band points to a UK H (US K). Treat it as a starting size and let the fit checks decide.

What bra styles work best for a 34H?

Anything built around a firm band and structured cups — three- or four-part seamed cups, or moulded cups with a side sling. Wide, cushioned straps and tall side wings stop grooves and spillage. Under knits, a t-shirt bra with a sling gives structure without a visible seam.

Do you carry 34H sports bras and strapless?

Yes. For sport at 34H, choose an encapsulation style with separate structured cups rather than a compression crop. For strapless, look for a longline or firmer band with silicone grip. Browse sports bras and strapless.

My 34H doesn't fit — what's wrong?

Usually one of two things: the band is too loose (it rides up and the straps dig), or the size was converted wrong from another system. Re-measure, confirm whether the brand is UK- or US-sized, and try your sister sizes. Our size conversion guide resolves most cross-system mix-ups.

Sizing guidance here is general. Bra sizing is not standardised — cup labelling, wire shape and band firmness vary by brand and style, so conversions are a starting point, not a guarantee. Always check the individual brand's size chart and treat any measurement as a place to begin. Size availability reflects current stock. Last reviewed July 2026.

Shop 34H bras

A UK 34H (US 34K) in t-shirt, strapless, sports and full-figure styles — firm bands, structured cups, and straps that stay where you put them.

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