Are you a 30?
If your underbust measures between 29 and 31 inches (74 to 79 cm), yes. If you currently wear a 34 and it rides up or is on its tightest hook, there is a good chance too: a 34 band is four inches longer than a 30-inch ribcage.
The usual objection is the cup letter. Moving from 34B to the equivalent volume on a 30 band gives 30D, and if the cups were also a little small, 30DD or 30E. Those are modest sizes. The letter is larger only because the band is smaller.
30-band sizes
| Size | Bust | Same cup volume as |
|---|---|---|
| 30B | 32 in (81 cm) | 32A and 34AA |
| 30C | 33 in (84 cm) | 32B and 34A |
| 30D | 34 in (86 cm) | 32C and 34B |
| 30DD | 35 in (89 cm) | 32D and 34C |
| 30E | 36 in (91 cm) | 32DD and 34D |
| 30F | 37 in (94 cm) | 32E and 34DD |
| 30FF | 38 in (97 cm) | 32F and 34E |
| 30G | 39 in (99 cm) | 32FF and 34F |
| 30GG | 40 in (102 cm) | 32G and 34FF |
| 30H | 41 in (104 cm) | 32GG and 34G |
Where 30 bands are stocked
Availability is better than for 28 bands and still patchy. Ranges change, so treat this as a guide to where to look first.
- Full-bust brands: Freya, Panache, Cleo, Curvy Kate and Bravissimo's own label all make 30 bands as standard from a D cup upward.
- High-street lingerie chains: Boux Avenue's range starts below 30. Some M&S, Primark and other chain ranges include a 30 band in selected styles, usually in a limited run of cups.
- Department stores and online lingerie retailers that carry the full-bust brands.
- Independent lingerie shops.
The awkward cups
The easiest 30-band sizes to find are 30D to 30G, because full-bust brands make them. The hardest are 30A and 30B, which fall between the mainstream ranges that start at 32 and the full-bust ranges that start at D. Petite and teen ranges, and retailers whose sizing starts at 28A or 30A, are the places to try.
Shopping tips for a 30 band
- Filter online by band first. It shows immediately which styles exist in your size.
- Check band firmness in reviews. A brand with stretchy bands may leave you wanting a 28. One with firm bands may be right at 30.
- Mind the wires. On small bands with fuller cups, wire width matters. If wires poke under your arm, look for narrower cuts. See underwire poking your armpit.
- Buy two when you find one that fits. Styles in less common sizes are discontinued without much notice.
If your size is not available
The 32-band sister size, one cup down, is the fallback: 30F to 32E. Fasten it on the tightest hook. It will not support as well as the 30, particularly with a fuller cup, so keep looking for the real thing. More on small-band, fuller-cup shopping in small band, large cup bras in the UK.
Frequently asked questions
Is a 30 band small?
It is at the smaller end, and it is not rare. It fits a ribcage of about 29 to 31 inches, which is common among slim and petite adults. It seems unusual mainly because many shops start their ranges at 32.
Why do shops not stock 30 bands?
Stocking every band in every cup is expensive, so many chains concentrate on 32 to 38. Sizing methods that add inches also hide the demand, because people who would fit a 30 are sold a 34.
What is the sister size of a 30 band in a 32?
One cup letter down. A 30E has the same cup volume as a 32DD, and a 30DD the same as a 32D.
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