How to choose a correct skirt/trouser pattern size using body measures and finished garment sizes

How to choose your correct skirt or trouser pattern size based on your body measurements, and finished garment sizing.

The most important thing to remember about sewing from Commercial patterns is that the sizing is VERY DIFFERENT to High street ready to wear sizes. Generally the big american pattern company sizes are about 2 sizes smaller than British High Street sizing. The only way you can get good fitting clothes from a pattern is to compare your own body measurements with the size chart provided on the pattern.

To get a really good fit, you need to look at the pattern sizing in 2 steps.In this post i’m only discussing choosing sizes for skirts or trousers.

Step 1- will help you buy the correct pattern pack. Patterns are often sold in 2 size ranges, so you want to make sure you’ve selected the right one!

  • For a skirt or garment for your lower body, you’ll be basing the overall size selection on your hips measurement. You will then blend from the hips to your waist size. This means the skirt will fit your frame, and you’ll be either adding or taking away at the waistline. The last 2 columns on the first chart refer to the pattern size closest to each of your body measures, and this will help you easily draw between pattern sizes.

For example- you may be closest to a 10 at the waist and a 14 on the hip. As in my example below.

Chart 1- Basic pattern size

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Step 2- Understanding “design ease’ and using Finished garment measures to fine tune your fit and size selection.

  • All clothes need wearing Ease! If you cut a skirt to exactly the same size as your body measures, then it’s impossible to breathe or walk! You need all your clothes to be a little bigger than you, so they’re comfortable to wear. I’ve added the minimum ease in Chart 2 below
  • The final bit of fine-tuning to will think about when choosing a size is the amount of “Design Ease” that’s been allowed in a pattern. Design Ease is the amount of extra fabric in the garment over and above your own body measurements. If you compare your actual measures plus wearing ease with the finished garment measures for each pattern you use, you’ll be able to see how fitted or baggy the garment will be. You can choose to go up a size if the pattern has come up tight, or down a size if the pattern seems very loose.

NB- If there are no finished garment measures on your pattern skip this step, and work out your pattern size from Chart 1 only and tissue fit before cutting your fabric.

Chart 2- Use Finished garment measures to fine tune size

One of the best tips I’ve found for working with finished garment measures, is to measure your favourite clothes! Making a Tee shirt? Why not measure the one you’re always wearing and use that as your benchmark for how much design ease you’d like in your new Tee shirt. It’s a good idea to make a little chart of your fav clothes, and compare new patterns to your old favourite clothes.

To help you understand design ease, I’m going to show you 2 examples, both skirts, and we’ll look at the hip measures to choose our final size

Example 1-

This skirt is a slim fitted pencil skirt, so I don’t want a lot of design ease over the hips, as this will look unflattering

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The envelope back has the garment measures on it (although not the waistline). I’m working with a 25 inch waist and a 38 inch hip. See the ringed illustration.

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In this example I can see that the finished garment measures for size 14 is 3 inches bigger than my hips. I need  to allow 1.5 inches of wearing ease, which takes me to 39.5 inches, so that leaves 1.5 inches of total design ease around the hips on this pattern. In this instance I’d cut my hips to the 14, and fit as i sew if they are a little too big.

Example 2-

This is a classic A line skirt.

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The finished garment measures are not on the back of the envelope, they’re printed onto the pattern pieces themselves. Some brands even show how much design ease there is too as a printed number!

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Again using the same measures I’ll compare my base pattern sizes to the finished garment measurement.The finished garment measurement for the 14 at the hipline is 42.5 inches, a whopping 3 inches of design ease around the hips. In this instance, i’d definitely cut the hips to a 12, as the finished measures for the 12 is 40.5 which will give me a closer fit.

Here’s a little chart for you to use with suggested wearing ease included.Remember to do this for EACH pattern you work with.

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How to measure yourself.

Wear close fitting clothes like a vest top and tights, or underwear.

  • Put your hands between your hip bone and rib cage and bend from side to side, This will help you find your natural waist. Most fashion dictates that clothes rarely sit right on the natural waist, But all patterns have been cut from this measurement unless they state otherwise.
  • Make sure the tape measure is snug. Too tight or too loose and you’ll get the wrong size.
  • When you take the measurements, keep the tape measure horizontal, and try and look straight ahead, so you don’t bend forward

These are the main measurements you’ll need to determine pattern size.

How to choose a correct skirt/trouser pattern size using body measures and finished garment sizesHigh bust- this is your chest measurement and is really close under your arm-pit, above the fullest part of the bust-line


Full bust- this is taken around the fullest part of your bust


Waist- this is your natural waist measurement, and is taken at the position of the elastic you tied around your waist


Hips- the fullest part of your bum, NOT the top of your hip bones


Use your favourite clothes to help you adjust your pattern

EG- If you always need to shorten your skirts before you can wear them then you’ll need try checking the finished length measurement of your favourite skirt against the pattern pieces, and shorten the pattern to match. Likewise if you know you’ve got long legs then you’ll need to lengthen the pattern pieces.

By altering the pattern pieces before you even lay them on the fabric, you are already making a unique pattern piece tailored just for you 

Blending between pattern sizes

Use your experience of clothes shopping to help you adjust your patterns. always buy for your waist and end up with baggy hips? Or the opposite do you need to buy for your hips and end up with a baggy waistline? Both of these examples show that your figure crosses at least 2 sizes. Few of us are exactly the same size as the standard pattern sizing.

The beauty of dressmaking is that you can blend a pattern between several sizes to get a custom fit!

blending between sizesLet’s say your hip measure is close to 14, but you’re 10 at the waist. Trace the biggest size (14) from the hipline down. Then using a ruler draw a new shaped line from the hips to the waist. Your traced pattern is now tailored to your own unique body measures.
Itching to make pattern work better for you? Why not come to our commercial pattern class where we’ll guide you through the basics, and show you a few common pattern alterations.

Happy Stitching:)



  • irene

    31.01.2015 at 20:43

    This is a great piece of imformation. i am having difficulty with skirt patterns as it would appear my waist size of 37 inches doesn’t feature in any patterns! My hips are 40 inches. This is making me disheartened and I am now afraid to sew anything else having made a lovely size 14 skirt for it to be about 4 inches too small on the waist (I will never lose that much weight!)
    Thank you for any help you could give me
    Irene x

    • Linda

      18.02.2015 at 19:50

      Hi Irene
      Exactly the same problem..37″ waist and 38″ going to have a go altering the pattern but will need to add quite a bit at the waist…what I can’t understand is that a size12 White Stuff skirt fits me perfectly! Would, like you, appreciate some tips, Linda

      • The Thrifty Stitcher

        18.02.2015 at 22:11

        Hi Ladies,

        i like you have a waist that’s larger than the standard difference between waist and hips. My hip is 38, and waist is 31. I cut a size that matches my hips, usually pattern 14 if i use an american pattern like simplicity or MacCalls. I then blend my hips from the smaller 14 out to an 18 at the waistline. If the pattern isn’t in the right size range for my waist, i add the additional amount needed by sticking paper on the edges and then re-drawing between the hips and waist.
        A 37 inch waist is usually an american pattern size 22. If you don’t have that size in the pattern, you need to do a little maths. Irene, with a 40inch hip, select the size closest to the 40 inches, usually an american pattern size 16. you then need an extra 1.75 inches of paper added at the waistline on the front and back pattern pieces
        Hope that helps?

        Linda, White stuff use a totally different sizing system than sewing patterns, so a 12 in that shop doesn’t equate a pattern size 12. As all pattern companies have different sizing system, you need to ALWAYS compare your body measures to the pattern sizing

        Best wishes:)

        • Linda

          20.02.2015 at 18:59

          Thanks for the tips..especially about adding paper to the sides..I have cut size 14 pattern and will adjust the waist..I thought it might be useful to measure a skirt that fits and go from there.
          Thanks again, Linda

  • Alice

    15.01.2015 at 21:06

    Great tips, thank you for sharing!

  • Jill Young

    14.01.2015 at 09:38

    I found the tips about size and patterns really helpful. thank you.
    I have had a few disasters with skirt making and have not attempted making trousers but will have a go now.

    • The Thrifty Stitcher

      14.01.2015 at 14:08

      Hi Jill,

      Thanks for your comment, and good luck with the dressmaking. The trick is perseverance, keep going and i’m sure you’ll have more success stories than failures
      Best wishes :)