how to measure the right bra band

The band size of a bra explained | 3 Steps to get the right bra band

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Your bra size is built on two measurements. Start with the first step, measuring your underbust. Find your band size in 3 easy steps


How to determine your bra band in 3 steps

There are about 14 different band sizes available.

Although not every brand has the whole range of band sizes 28 – 54.


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Step 1. Measure your bra band size

drawing of woman showing how to determine the bra band
Hold the tape horizontal


The smaller the band size you need, the smaller your underbust is.

For the band, measure directly under your breasts. Hold the measuring tape horizontally. Looking in a mirror will help.

measure tape used to determine a bra band size

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My advice is to measure a couple of times and write down the outcome.

It’s normal if you measure slightly different outcomes. By measuring a couple of times you can decide on the best measurement.

Measuring from your own home isn’t difficult. Ask someone to give you a hand if you like.


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Step 2. Check the feel of the band

woman fastening her back bra band
The most support comes from the band

It could be your measurements are in between two band sizes. You could round up to the nearest whole number.

  • your band size should be firm but not too tight
  • when you wear your bra for some time the band should still feel firm but comfortable
  • do remember that the most support of your bra comes from the band


Step 3. Try different band sizes

Happy with the feel of the bra band? Does it feel supportive, but not too tight? That’s great.

Maybe you’re not sure and think you might need a smaller or wider bra band.


Going up or down a band size will automatically change the cup volume as well.


This happens when you go up a band size

You wear a bra 36C and want to go up a band size. You choose a band size 38. But when going up a band size the volume of the cups will change too. A 38C bra will have more cup volume than a bra in 36C.

If you want to keep the same cup volume you should try 38B.


This happens when you go down a band size

You wear a bra 36C and want to go down a band size. You choose a band size 34. But when going down a band size the cups will change too. A 34C bra will have less cup volume than a bra in 36C.

If you want to keep the same cup size you should try 34D.


Also, keep in mind that different brands may be sized a bit differently. If you know your bra sister size it will help you to know what sizes you wanna try.


Other articles you might like

Bra Measuring Guide
The average bra size in the UK
Why is my bra hurting me?
What is my best bra size?
UK bra size chart
Can I buy a bra without measuring?
The average bra size UK


What's your bra size? See my calculator

Marks and Spencer Lingerie

Find the right bra at your M&S Store
M&S UK | M&S US | M&S CA | M&S AU