US to UK conversion

34C in UK Bra Size

Convert 34C from US sizing to UK sizing, with the full international table, nearby sister sizes, and fit checks in one place.

Instant answer

34C (US) =

34C UK

In this sizing table, 34C in US sizing converts to 34C in UK sizing.

Sizing varies by brand

A conversion gives you the closest label in another sizing system, but brands can grade cups, wires, and bands differently. Use the converted size as a starting point, then check the retailer's chart and the fit of the actual bra.

Before you buy in UK sizing

Use 34C as the translated label, not as a fit guarantee.
Check the retailer's size chart because some brands grade bands and cups differently.
If the cup volume feels close but the band changes, compare sister sizes before switching cup letters.
When possible, check return rules before buying across sizing systems.

Full conversion table for 34C

34C bra size conversion across US, UK, EU, French, and Australian sizing.
US	UK	EU	FR	AU
34C	34C	75C	90C	12C

Bra sizing varies between brands. Use this as an accurate starting point and check the fit.

Sizes near 34C in UK sizing

If 34C is close but not right, these are the neighbouring US sizes and what each one becomes in UK sizing. Band neighbours change the fit around the ribcage; cup neighbours change volume.

US sizes adjacent to 34C and their UK equivalents.
US size	UK size	How it differs
32C	32C	One band step snugger, same cup letter.
36C	36C	One band step looser, same cup letter.
34B	34B	One cup step down, same band.
34D	34D	One cup step up, same band.

What this conversion means

A US 34C means a 34 band with a C cup step. The UK equivalent in this table is 34C, which keeps the same general fit target but uses UK labeling. If the cup feels close and the band feels off, sister sizing is usually the next thing to try.

Sister sizes for 34C

Sister sizes: 32D and 36B can be worth checking when the cup volume feels close but the band needs a different feel.

What measurements make a 34C?

34C starts with the underbust, then adds cup depth from the bust measurement. In the current calculator formula, the closest starting range is about 33-35 inches (84-89 cm) under the bust and about 36.5-37.5 inches (93-95 cm) around the fullest part of the bust. The band comes from the underbust rounding, while the cup step comes from the difference between bust and band.

Is 34C big or small?

The label 34C can look more dramatic than it fits, especially across systems. In this size set, the US equivalent uses a middle band and a middle cup step. Cup letters are relative to the band, so a D on one band is not the same volume as a D on every other band. The most useful question is whether the band stays level and the cups hold smoothly, not whether the label sounds large or small.

If 34C doesn't fit right

Band rides up: The band may be too loose or stretched out; try a snugger band or compare the snugger sister size.

Cups gape: The cup may be too roomy, too deep, or pulled away by a loose band; check the band before changing cup volume.

Cups spill: The cup volume may be too small or the cup shape may be too closed; try one cup step up before changing the band.

Straps dig in: The straps may be compensating for a band that is not supporting enough; reset the band fit before tightening straps.

How 34C differs between brands

Brand sizing matters for 34C because cup depth, wire width, and band stretch are design choices. A firmer elastic can make the same band feel smaller, and a shallow or narrow cup can make the same cup letter feel different. Check the retailer chart, read fit notes when available, and compare the label against the brand and region sizing guide before treating the conversion as final.

Shopping for 34C

A good shopping path for 34C starts with everyday support, then moves into outfit-specific shapes. If the cup is in a lower or middle step, lightly lined T-shirt styles can make gaps easy to spot. Fuller cup steps often benefit from styles with steadier side support, deeper cups, or a balconette shape depending on breast shape. For special outfits, compare the fit needs in the outfit guides before choosing a strapless, plunge, or backless option.

Bras in your size

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Everyday Fit Store

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Comfort Band Co.

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Soft Cup Edit

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FAQ

Is 34C in the US the same as UK sizing?

Not exactly. 34C is the US label, and this table converts it to 34C in UK sizing, though some brands publish their own charts.

What is 34C in European sizing?

In this same table, 34C converts to 75C (EU). That helps when a retailer shows a European chart instead of a UK one.

How do I know if 34C fits?

Check that the band stays level, the cups do not spill or gap, and the center gore sits close if the bra has wires. If the cup feels right but the band feels wrong, try a sister size.

What sister sizes work with 34C?

32D and 36B are the closest sister-size options for 34C in this dataset. Try a sister size when cup volume feels close but the band needs to feel snugger or looser.

Why do bra sizes differ between countries?

Countries and brands do not all use the same band labels or cup-letter sequence. A conversion translates the closest standard label, but the final fit still depends on the specific bra.

What measurements usually make 34C?

The current calculator formula points to about 33-35 inches underbust and 36.5-37.5 inches bust, or roughly 84-89 cm and 93-95 cm. Treat that as a starting range and then check the real fit.