Sports Bra Sister Size Guide

All about sister sizes

Sometimes you just can't find the right fit, no matter how hard you try or how many times you measure yourself.

All our bodies are different and sometimes this means our usual go-to-size doesn't work for a particular bra, but don't despair, that's what sister sizes are for!


What are sister sizes?

Sister sizes are alternate sizes to your usual fitting where your cup volume stays the same even though the band and cup letters are changing. In theory, as long as the cups on the bra feel correct but the band feels too loose or tight, sister sizing can quickly help you find the better fit.
To achieve this you have to shift your size in one size increments in opposite directions.

Here's an example:

Any Questions?

What if my cups and band don't feel right from the get go?

First of all, try to find your sister size in your band. Once you've found a sister size band that works for you, try going up or down by one cup size.

How do I determine if I should go up or down a sister size?

This depends on how your band feels and where you fasten it.
If you're on the tightest fastening possible and still feel loose
try going a sister size down.
If you're on the loosest fastening possible and still feel it's too tight
try going a sister size up.
*Remember your band should fit you on its loosest hook and eye fastening. It shouldn't be too tight or too loose at this fastening to be the right size for you.

My sister size didn't fit Should I go up or down more?

We recommend you don't go more than once down or up with sister sizes. If you're still not sure if the bra is the right size for you, please contact us and speak to one of our fitting experts.

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