The best and easiest way is to call into the store and be professionally fitted. If that’s not possible here is a useful guide to help you.

Wear the best fitting bra you have, preferably not padded.

Measure underneath your bra on your rib cage pulling the tape measure firmly. Making sure tape is level and not twisted. Round up to the nearest inch. If this number is an odd number add 5 inches to measurement, if even add 4 inches to the measurement. eg if you measure 32 under bra measurement this is an even number so when you add 4 inches to it this, you would be a 36 band size.

Next Place the tape around the fullest part of your bust holding the tape not to slack or tight, make sure tape is level and not twisted. Round up the measurement to the nearest inch. The difference in inches is your cup size.

Eg. The same size would be a AA cup

one inch would be an A cup

Two inches would be a B cup

three inches would be a C cup

four inches would be a D cup

And so on.

So for example if your band size is 36 and bust measurement is 40 that’s four inches difference so you would be 36D.

Please note this is only a guide.