I have fitted so many women that the measurements on my tape measure have worn away! Whilst your measurements are a great place to start when working out your size there are other elements to consider when choosing your lingerie.
This is a really personal preference and every woman is different, some women like to feel very held in with a firm underband fit whereas some prefer a looser fit. A lot of women have different sized breasts; most often the left is bigger due to the heart muscle. I think it’s best to accommodate the larger breast.
Think about the type of fabric you want to wear directly against your skin; if you are unlikely to wear a non-breathable fitted polyester tee-shirt then don’t buy lingerie in these fabrics. Laces, mesh fabrics and tulles are all made from polyamide which doesn't allow your skin to breathe.
Our bodies are constantly changing and fluctuating in size with our cycle, buying lingerie in materials that have stretch allow you to feel comfortable during these changes
I would never buy a bra that didn't have adjustable straps, nothing drives me crazier than a strap that isn't doing its job, the whole fit of the bra relies on a good quality strap. The strap should feel firm but not dig in and hurt. If your breasts differ in size, the strap on your smaller breast may need to be shortened to give the cup a smooth fit. Good quality rings and sliders allow you to adjust to the right fit for your body and keep the strap from slipping.
Having a triple hook and eye is really important as there’s no one body shape and the option of 3 fastening widths allows you to customise the underband fit. There is a myth that you should be on the tightest hook so that you can move out a row if the bra stretches out of shape; if a bra is constructed from high quality elastics and has a good powermesh liner in the back wing it won’t stretch out of shape and being on the tightest hook is not an issue if this is the position that fits your body best. A bra with no back fastening that you pull over your head and shoulders daily will soon stretch out of shape.
The flexibility needed for changes and fluctuations in size need to come from the cup capacity. Unless you are going through a life change like pregnancy your rib cage isn’t adjusting it’s your cup size. Buying a bra with a darted or seamed cup and a small amount of stretch in the fabric allows for shape in the cup.