Fitting Advice

Bra Fitting
Let’s talk boobs

Most of us need to wear a bra, at least sometimes. But lots of women I speak to complain about how much they hate bras - they don’t find them comfortable at all. Many seek out the advice of a “professional bra fitter” in the hope of finding a better fit. Sadly this often doesn’t help.
There are a few shops out there who are doing it right - Bravissimo, Rigby and Peller, Leia etc. But there are a lot more who are doing it wrong. Marks and Spencer, BHS, AnnSummers, La Senza and many others are on the bad fitters list. If you have had a fitting from any of them, or followed almost any online size chart, then chances are you are in the wrong bra. If you recognise any of the symptoms below then you probably need a new bra. 

  •  You have to tighten the straps a lot to keep the bra up
  • Your bra rides  up at the back - you can feel it isn't sitting horizontally
  • Your shoulder straps dig in and leave nasty red marks or grooves
  • Your bra straps fall down (off the shoulder)
  • You sometimes bulge over your bra (the 4-boob look)
  • If you lift your arms, your bra moves up (sometimes letting you slip out from underneath)
  • You have “armpit fat” - there is bulging over the sides of your bra cups.
  • The middle of your bra (the “central gore”) does not sit flat against your chest - it should sit flat in between your boobs
  • The wires dig and cut in - anywhere
  • You suffer from back  or neck pain
  • Your bra slips down, leaving empty space at the bottom of the cup
  • You are a size 8 and wearing a 34 band…it’s possible, but it’s unlikely!
These are all signs of an unhappy bra. 

The reason for this is an old fitting method where they take your back measurement and add 4-5 inches to get the back size. This results in an unsupportive and often painful bra, normally much too big in the back and too small in the cup. 


Firstly, you can’t get your exact size from a measuring tape. You can get a pretty good guide (particularly when it comes to the back size) but you need to know what to look for to get it perfect. First off - getting your “starting size”; you can measure wearing a bra, but only if the bra already fits well. So I am going to tell you how to do it braless.

1.     Measure underneath your bust, firmly, in inches. The tape measure should be pretty tight 2.     Bend over so your boobs are hanging down at 90 degrees and measure round the widest part - like this picture

The underbust measurement is the band size*. If you are an odd number you will want to try the size either side to be sure, but as a rule of thumb most people fit better if they round down. So, if you measure 31”, you could try a 30 and a 32 back, but chances are the 30 will be better. 

*there are a couple of exceptions to this rule. If you are very very slender and have no “padding” around your ribs then you may find it necessary to try one back size higher. Conversely, if you are “squidgy of torso” then you may need a smaller back size than you actually measure as the bra needs a relatively firm surface to sit on. So if this is you don’t be scared to try 1-2 back sizes smaller than you measure. 

To test if the band fits:
Put the bra on back to front so the cups are at the back. When new this should be on the loosest hook as bras stretch with age. The band should feel snug, and you should be able to fit a couple of fingers under it, but that’s about all. If you can’t breathe try a size up,  but most of the support comes from the band so we are aiming for firm. The reason for  trying it back to front, is that even if the back is correct, if the cup is far too small it can trick you in to thinking the band is too small - the cups try  to steal the fabric!

Now, working out the cup size:
Most UK manufacturers Bra-lphabet goes A,B,C,D,DD,E,F,FF,G,GG,H,HH,J,JJ,K,KK,L…..there is also the AA, which is smaller than an A. For each inch difference between your band size and your overbust measurement, you get a cup (starting at A) - so somebody measuring 30” underneath and 40” over would start at a 30GG. I would normally suggest trying AT LEAST 1 cup size either side of this to be sure. Now, if you have always been fitted the “old way” you will probably be in shock right now, as you’ve probably gone down 2-3 back sizes, and up several 

Once you have the band right, time to test the cups. Here is what to do:
Lean forward, drop your breasts in to the cups and do the bra up at the back. Now, take your right hand, put it round inside the left cup, all the way round under your armpit, and scoop all the soft tissue and flesh in to the cup. You might not know it, but all that soft tissue under your armpit is breast, and it needs to be in the cup. Now, repeat on the other side. The wire should totally encase your soft breast tissue, and you should have no overspill or wrinkling in the cups. The central gore should sit flat in between your boobs. 

I am going to put up another post later showing good and bad bra fits.


  1. I really liked this blog and wanted to link it to my FB page. But when I did, the preview showed the first comment above - totally inappropriate. It might be an idea to approve your comments first before they appear, just to avoid this, because it's a pity to spoil your blog with these stupid inappropriate comments from weirdos.

  2. I think the comment only appeared today and has already been deleted. Unfortunately there are spammers everywhere

  3. I think the comment only appeared today and has already been deleted. Unfortunately there are spammers everywhere

  4. Hi,

    I've been wearing a 36AAA bra from a specialist online shop for the last year and before that I was on 36A from M&S. I had basically given up on ever having a bra that fits because my breasts were too small and had no confidence in how they looked.

    After reading this guide I went of a shopping trip and have come home with 34B bra's that fit me so much better but I've never even considered a B as I never seemed to fit even an A properly.

    Thanks :)

  5. Well this has been slightly helpful! I am a size 8 and have been wearing a 34DD for years. However, the cup size is far too small and I even fall out of the bra when I walk! However, after measuring using this method I have discovered I would fit into a 30 band, but I have yet to find my cup-size. However, I imagine I will no longer be able to buy bra's from New Look.

  6. Hello I am 22 weeks pregnant at the moment and had been measured by M&S as 36 DD I am 33 underneath and 44 when I hang forwards, I still can't make head nor tail of what I should be bra size wise . Can you help? I think from this I would be a 32 0r 34 H is that right? It seems odd as the back band on the 36DD feel tight already :-(

  7. As you are pregnant so ribs likely to expand more I would round up and start with a 34gg and 34h and work from there. Pregnancy is the one time to buy your bra so it fits on the tightest hook. The reason the 36 feels tight is that it is far too small in the cup so the cups are pulling the band fabric

  8. Ohhh I went down one back size and up from a D cup to a GG!!! Dying to try out a new size as soon as possible to see if this works for me xx

  9. Maybe I'm reading your instructions for measuring wrong, but if each inch over band size represents a cup, then wouldn't someone who' s measurements are 30/40 start at 30E and not 30GG?

  10. oops, ignore my comment! apparently I can't count. Not being able to find a bra that fits has frazzled my brain.

  11. I have measured and re-measured myself using your method and it just doesn't seem right.

    My measurements are;
    Tight - 37
    Snug - 38.5
    Standing - 50
    Leaning - 54

    I am currently wearing a 42H that rides up at the back with 2-3" of room when clasped at the tightest, it also give me the four boob effect.

    Your calculator has put me at a 38K, however i have tried 3 different designs and makes and in all of them the cup size has been ridiculously big. In a 38K balcony bra i tried on the top of the cup sat just an inch under my collarbone! The band size (38) however fits me beautifully.

    So can you please tell me what bra size i should try because the K is far to big. I have just ordered a 38J to try, hopefully that will give me more of an idea what size i actually am.

    1. It's odd that you are finding the K so big- if your 42H is currently much too small in the cups. Using sister sizing then a 42H should have equivalent cup volume to a 38J so I'd expect you to be larger than a J based on your description.

      In terms of measurements the the cup can only ever be an approximation and it becomes less accurate at larger sizes too as there's more variance I'm shape and a bigger absolute measurement. As a method it's correct om average unlike the old plus 4 approach but there's a spread of fits around the measured size

  12. Hi, I'm kind of confused and wonder if you can help. I've been wearing a 24B until now. Just measured in your way and came out as a 30G! (I'm 31 around the ribs and 37 bust). Even jut looking at a G in the shop looks crazy compared to what I have. Am I working that out wrong please?

    1. You've missed a few cup sizes, in UK sizing you would be looking at trying 30e, 30f, 32e or 32dd.