French seams are generally used for lightweight and sheer fabrics such as silk, organza and chiffon, where traditional seam finishing methods would show on the right side of the fabric. They are also great for items that will be washed repeatedly, such as pillowcases. Read this easy how to sew a French seam tutorial.
What are French Seams?
French Seams are a type of seam finishing used in sewing where the raw edges of the fabric on the inside are totally encased in an extra row of stitching. This creates a seam that is far more durable than most other seam finishes and an item or clothing pieces that looks as attractive on the inside as it does on the outside.
What are French Seams Used For?
French seams are generally used on straight seams rather than curved seams. It can also be used on corners successfully. It is better suited to thin to medium weight fabrics as heavy fabrics add too much bulk in the enclosed seam. Further Reading: Sewing Curves and Clipping Sewing
Use a French Seam for:
- Pillowcase seams since they will be washed repeatedly
- Sheer fabrics where the edge would otherwise fray and look unattractive
- Garments with delicate, fine fabrics such as silk and chiffon where overlocking or zig zag would create unwanted bulk and show stitching through to the other side.
- Linen seams where the edges would fray excessively
- Straight side seams on kids' clothing. Kids' clothes get washed far more, so durability is really important.
French Seams - How to Sew A French Seam Video
Here is a quick video I made to show you just how quick and easy French seams are to sew. Like most of my videos, it is only about 3 minutes and gets straight to the point. I know you are busy! Subscribe to my YouTube channel for weekly sewing and craft videos.
French Seams - Photo Tutorial
Here are the steps for the how to sew a French seam tutorial. Grab a piece of your scrap fabric first to practice and to ensure this is a suitable seam for your sewing project.
STEP 1 - Sew the Seam
Pin the WRONG sides of the fabric together.
IMPORTANT (French seams vs Regular Seams)- This is the biggest difference between sewing French seams and regular seams. Normally you would start with the RIGHT sides together to stitch a seam. With French seams, you start with WRONG sides together. It can seem a little strange at first, but you will quickly get used to this difference.
Align the sewing machine presser foot and stitch the first seam. Your seam allowance should be ¼inch (6mm) less than the seam allowance specified in the pattern. If your pattern has small seam allowances less than ½ inch (12mm), it may be necessary to add a little extra.
- For a ½ inch (12mm) seam allowance – sew now at ¼ inch (6mm) from the edge
- For a ⅝ inch (1.5cm) seam allowance – sew now at ⅜ inch (10mm) from the edge.
STEP 2 - Trim the French Seams
Trim seam allowance to ⅛ inch (3mm). Use sharp scissors to get a nice clean edge and do your best not to overhandle the raw fabric edges in the next couple of steps to prevent them fraying again.
Trimming Corners: If you are sewing French seams on an item with corners (for example on pillowcase corners), make sure you also trim the corner diagonally to reduce the bulk.
STEP 3 - Press Seam Open
Press open the seam with the seam allowance on one side. Make sure the seam is nice and flat. Use an up and down pressing motion rather than pulling the iron along the seam. Further reading: Pressing for sewing
STEP 4 - Press Right Sides Together
Press the fabric in half with RIGHT sides together and with the seam on the edge. Make sure the seam is on the very edge and not to the side as all for the best results.
STEP 5 - Second Stitch Line for French Seams
Sew the second seam ¼ inch (6mm) from the folded seam edge. Using a ¼ inch foot (6mm) may help keep your width accurate.
The previous seam allowance and layers of fabric will be sandwiched in the fold. It is important to sew the second line of stitches accurately or you will get little tufts of raw edges poking through the seam.
STEP 6 - Final Press
Press the seam open again, with the seam allowance on one side. Flip your piece over and give the inside of the seam a final press so it is nice and flat.
You can now get a professional French seams finish on your next project!
French Seams for Curves
Although french seams are best on straight seams, it is possible to use them on very gentle curves.
If you do want to do French seams on a gentle curve, pay special attention to step 2 where you will need to trim as close as possible to the seam. In addition, put some tiny clips into the seam allowance in step 2, being careful not to cut into the stitching line. (Read Clipping Sewing)
French Seam FAQs
What is the disadvantage of the French seam?
The main disadvantage of French seams is that you can't use it on curved seams. Due to its constructions style, it is best suited to straight seams. The other disadvantage is that it adds too much bulk to thick fabrics.
Can you use French seams on a curve?
You can only use French seams on very gentle curves. If you have a curve for example, on an armhole, you will need to use another seam type.
French Seams Pillowcase Patterns
Now you know how to sew a French seam, why not test your new skills. I have a full blog article on how to make a French seam pillowcase.
These are really durable in the wash and a great beginner sewing project. Add some lace or trim to the edge to make it interesting and unique. Both of these pillowcase patterns have cutting instructions so you can make them in several sizes.
Pillowcase Patterns on my Blog
Why not try French seams on the side seams of the Taylor Skirt? This is a FREE tutu skirt sewing pattern!
- Sewing Supplies - needle, thread, scissors
- Scrap Fabric
- This is how the finished seam looks. See the encased seam on the wrong side and the smooth open seam on the right side.
- Put the fabric with wrong sides together. Stitch the seam ¼ inch (6mm) in from the seam allowance. (eg. sew at ¼" if the seam allowance is ½": sew at ⅜" if the seam allowance is ⅝")
- Trim the seam to ⅛ inch (3mm).
- Press open the seam. Fold the fabric, so the right sides are toghether and press along the seam. (Seam will be on the edge.)
- Sew the seam again ¼ inch (6mm) from the edge.
- Open the fabric and press the seam to one side.