What are the sister sizes of 30A?

28B — same cup volume, different band.

Is 30A the same in every brand?

No. A 30A can fit differently between brands because of pattern, fabric and cup shape. Use it as a starting point and try a sister size when switching brands.

30A bra size — conversion chart, sister sizes & brands

A 30A bra (US notation) in every regional standard. The same band-and-cup, labelled eight different ways.

US	UK	EU	FR	IT	AU	JP	IN
30A	30A	65A	80A	65A	8A	65A	30A

Band conversions are exact; cup fit still varies by brand, style, and body — a conversion is a starting point, not a guarantee.

Sister sizes of 30A

Sister sizes hold the same cup volume with a different band — the quickest fix when a band feels too tight or too loose.

28B

Not sure you're a 30A? Two measurements, two minutes — free, nothing stored.

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Brands that make A-cup bras

30A FAQ

What is 30A in EU sizing?: 30A (US) is EU 65A. In UK sizing it is 30A. Band conversions are exact; cup fit still varies by brand, style, and body — a conversion is a starting point, not a guarantee.
What are the sister sizes of 30A?: 28B — same cup volume, different band.
Is 30A the same in every brand?: No. A 30A can fit differently between brands because of pattern, fabric and cup shape. Use it as a starting point and try a sister size when switching brands.