Size Guide

48A Bra Size

Everything you need to know about bra size 48A — measurements, sister sizes, international equivalents, and fit advice.

Last reviewed on 28 April 2026.

Measurements for 48A

Underbust (Band)
47 to 49 inches (119 to 124 cm)
Full Bust
approximately 50 inches (127 cm)

48A is built for an underbust ribcage measurement that falls in the 47–49 inch range, with a full-bust measurement around 50 inches. The band number — 48 — is a fuller band size where most of the support comes from a strong, snug band rather than the straps. The cup letter — A — describes the difference between the two measurements; an A cup means the full bust is about one inch larger than the underbust — light shaping and bralette styles are common at this size.

48A in Other Sizing Systems

US
48A
UK
48A
EU
110A
FR
125A
AU
26A

EU and FR sizing read the band in centimetres, which is why 48A maps to 110A and 125A respectively — the same body, expressed in different units. AU sizing uses a small numeric scale (26A for this band). UK sizing shares the band number with the US but parts ways at the cup once you go past D, so 48A reads as 48A on a UK label.

Sister Sizes for 48A

These sizes have the same cup volume as 48A. Try them if the band feels too tight or too loose.

46B 48A

← Tighter band, bigger cup · Looser band, smaller cup →

Sister sizes are useful when the cup of your 48A fits well but the band is wrong — too loose by the end of the day, or too tight to clip up comfortably. Going one band smaller and one cup larger keeps the cup volume the same while tightening the band; going the other way loosens the band without losing cup space. Read the full sister-size matrix if you want to see how this works for every size at once.

Fit Tips for 48A

A-cup bras often benefit from light padding for shape, though many wearers prefer unpadded cups. Bralettes and triangle styles are common and comfortable for everyday wear.

If your 48A bra is gapping at the top of the cup, the cup may be too large or the wrong shape — try a demi-cup or balconette before assuming the size is wrong. If the centre piece between the cups (the gore) does not lay flat against your sternum, the cup is almost certainly too small; go up one cup. If the band rides up across your back during the day, the band has stretched out or was too loose to begin with — drop one band size and add one cup to keep the same cup volume.

For more detailed troubleshooting, the Fit Test on the home page covers six common visible problems and the size or shape change that usually addresses each one. The guide to measuring mistakes covers the most common reasons a calculation comes out wrong in the first place.

Related sizes

If 48A is close but not quite right, these neighbouring sizes are the most useful next places to look:

48AA · one cup smaller48B · one cup larger46A · one band smaller46B · sister size — tighter band

Not sure about your size? Measure yourself and double-check.

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