Sister Sizes
What is a sister size?
A "sister size" is a size that is different to your true bra size, but is still likely to fit you. The band will be bigger or smaller, but the cup capacity will remain the same.
When to use sister sizes
There are several sizes available when shopping for bras and bra-sized swimwear. If we do not stock your true bra size or if we are sold out of your size, you can find a sister size below.
Sister Size Chart
How to use sister sizes
You have two options, depending on whether you have room to go down in the band, or if you go up in the band:
1. Increase the band, and decrease the cup.
2. Decrease the band, and increase the cup.
Note: Both of these options will have a similar fit in the cup, despite the cup labels changing.
For example, if your true AU size is 12E/F, you can try 10FF/G or 14D/DD.
You can use our sister size chart below to quickly find your sister size. Following a diagonal line upwards, sister sizes are reflected in the same shade of pink.
Looking for support?
Lifeline
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Butterfly Foundation
If you or someone you know is struggling with an eating disorder or body image issue, call Butterfly’s National Helpline.