Sewing Blog

Seam Series: How to Sew a Flat Fell Seam Tutorial

Take a look at your jeans or at a men’s dress shirt, and you’ll spot flat fell seams. On the outside of the garment there is a pair of stitch lines, and on the inside of the garment, it’s all clean and tidy without raw seam edges. Ever wonder how they did that? Well here you go! Let’s learn how to sew a flat fell seam, so you can try it on your next project.
Seam Series: How to Sew a Flat Fell Seam

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How to sew a flat seam

Step 1: Pin the fabric of the seam together, wrong sides facing.

flat fell seams
Step 2: Sew the seam with the wrong sides facing at the project’s allotted seam allowance. This example is being sewn at 5/8″.

sew seam
Step 3: Press the seam open on both sides of the fabric. Be sure to set your iron for the type of fabric being used.

press seam
Step 4: Trim one side of the seam allowance down to 1/4″. Do not trim the other side.

Step 5: Press the untrimmed seam allowance over the seam and on top of the trimmed side.

Step 6: Fold the pressed side under, tucking the raw edge into the fold.

Step 7: Press the fold, making sure that the raw edge is fully tucked under and that the flap left is the same width along the seam.

press the fold
Step 8: Line up your fabric in your machine so the stitching is close to the fold.

line up
Step 9: Stitch along the edge of the fold, trapping all the raw edges inside.


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Marion Frazer

I have been a home sewer for years, and have done flat felt seams…but watching you do this technique, reminds me how easy it is to do correctly and the results come out perfect. Thank you so much…what a delight….Marion


Very neat seam:)


love, love, love this! I am definitely doing this in my next garment! Thank you for the tutorial xx

Quilt Dude

Thanks for this tutorial. I am a quilter, but am branching out into garment sewing, so I’m trying to learn different sewing and finishing techniques, so this is very useful. I’ve practiced the pojagi style on scraps, and the finish is very clean and polished, with the raw edges all enclosed – Is the flat fell seam different from the pojagi seaming technique?


Pojagi or Bojagi removes the need to waste fabric by trimming the seam allowance. I think it is a more economical flat fell seam. And just as easy.


Clean, strong, and lovely!
Thanks much 🙂


Thanks! I’m altering my least favorite dress shirt as my first project. I just got step 2 done…. I’m taking my time so the shirt will be wearable when I’m done.

Upani lokusuriya

Very useful…. thnkz a lot… ☺


I used thisin class ### thanks biach

Claire Anderson

Thank you for this you’ve made it look really simple!! Now to get practising 🙂

Jan Buchanan

How do you do the final stitching on a long sleeve? I don’t know how to get access to the seam, without also stitching through the opposite side of the sleeve.

Judy Misiewicz

I have the same question. Did you get an answer, Jan?


I do this by turning the sleeve inside out after you have done the first row of stitching and pressed it. You then do the topstitching down the inside of the sleeve pulling the rest of the fabric away from the foot as you go. It does bunch up and is fiddly but is doable. Narrow sleeves very tricky.


I just used this for a shower curtain and it looks amazing!!

Catherine Rodriguez

Hi Christine,
I forgot to tell you that I also used your tutorial here to help me figure out how to do a flat felled seam. When we were leaving class I mentioned that I tried to make a reversible Eucalypt with flat felled seams. But I meant to tell you that it was this tutorial that help me! Your tutorials are amazing!


two tips for a FFS…..

-That first seam showing is your bobbin side – make sure tension is perfect!
-The pro’s use a shortcut, they don’t trim, they just move the fabric over.

Jessica P


This is super helpful!
I’m making a corduroy overall dress and it looks like there is a similar technique used on the straps – but it isn’t two piece of fabric sewn together, it’s just the edge of one pice of fabric. Is there a name for this? Or do you have any advice?


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