Question 1

Is a 34B the same in every brand?

Accepted Answer

No - a 34B isn't identical across brands, because brands use different sizing systems and cup depths. Here's how a standard US 34B translates in the brands we track: ThirdLove 34B, Wacoal 34B, Panache 34B, Bravissimo 34B, Freya 34B, Elomi 34B, Glamorise 34B, b.tempt'd 34B, Fantasie 34B. SHEFIT, Kindred Bravely, ENELL size by their own chart instead of band/cup.

Question 2

What are the sister sizes for 34B?

Accepted Answer

34B's sister sizes — same cup volume, different band — are 32C and 36A. Try a sister size if the band feels too tight or loose but the cup still fits.

34B Bras

Your 34B across brands

How Perfect Wire Free T-Shirt Bra: Black

Vivid Attraction Underwire Bra: White

Vivid Attraction Underwire Bra: Black

Vivid Attraction Underwire Bra: Woodrose

Vivid Attraction Underwire Bra: Dark Purple

Back Appeal® Wire Free Bra: Black

Back Appeal® Wire Free Bra: Rose Dust

Vivid Attraction Underwire Bra: Soft Sky

Deco U W Moulded Strapless Molded Strapless Bra: Nude

Deco U W Moulded Strapless Molded Strapless Bra: Black

Tailored Molded Strapless Bra: Natural Beige

Tailored Molded Strapless Bra: Black

Comfort First Strapless Bra: Roebuck

Vivid Attraction T-Shirt Bra: Black

Vivid Attraction T-Shirt Bra: Woodrose

Vivid Attraction T-Shirt Bra: Dark Purple

Belle Balcony Bra: Black

Red Carpet™ Strapless Underwire Bra: Black

Red Carpet™ Strapless Underwire Bra: Roebuck

Rose Lace Unlined Demi Bra: Sea-Salt

Brand	How it runs	Your 34B →
ThirdLove	cups run generous	34B
Wacoal	true to size	34B
Panache	true to size	34B
Bravissimo	true to size	34B