6 surprising things you didn’t know about bra fittings

1. You can keep your clothes on. Most bra fitters can accurately measure your size on top of your clothes. Some stores may ask you to only wear a bra while they measure you, but few will ask you to completely undress above the waist.

2. It’s free. Bra fittings are offered free of charge in any lingerie store changeroom. They make their money off the bras they recommend you buy after the fitting.

3. You should get fitted every time you buy a bra, or every six months. There are many factors that can change breast size: weight gain, weight loss, pregnancy, breastfeeding and constantly-changing hormone levels are just a few. Get fitted every six months, or every time you shop for a new bra, whichever occurs first. The correct size might not fit properly in different manufacturers and styles, even if it’s the same brand, which is why it’s best to get fitted every time you shop.

4. You can measure your own bra size at home. You don’t need an expert if you’ve got your own measuring tape at home. There’s a simple formula to figuring out your bra size:

Band size: Wrap a measuring tape around your underbust (the ribcage area directly underneath your bust), making sure the tape is parallel to the floor. If the measured number (in inches) is odd, add five inches to the total. If it’s even, add four inches. This number is your band size. (It should always end up as an even number.)

Cup size: Wrap the tape loosely around the fullest part of your bust, crossing your nipples. Take this number (in inches) and subtract your band size total from it. Each inch in the difference is a cup size. For example, if my bust measurement is 39” and my band size total is 36”, the difference is three inches and my cup size would be C.

Less than 1” / AA 1” = A 2” = B 3” = C 4” = D 5” = DD 6” = F

5. Three out of four women are wearing the wrong bra size. According to a survey done by lingerie company Triumph International, 76 percent of women are wearing the wrong bra size. Chances are, you might be one of them. To test this, four Chatelaine staffers (of varying chest sizes and body types) went for a fitting. Funnily enough, three of us were wearing a cup size smaller than we should have been, and one of us found she could wear a “sister size”.

6. If they run out of your size, you have sister-size alternatives. If the size a fitter tells you (or one you measured yourself) isn't available then consider a sister-size as an alternative. Because cup sizes are relative to the band size (the cup in a 36C bra wouldn’t be the same size as the cup in a 32C bra, for example), you could wear a different “sister-size” and still have it fit sufficiently.

To find your sister-size, read diagonally. Sizes in the same colour correspond to the same cup volume.

(Note: Sister-sizes aren’t ideal and should only be used as an alternative when your true-size isn't available.)

Read more: 10 tips to finding the perfectly fitted bra