Flat Felled Seam vs French Seam: Top Key Differences!

Flat felled and French seam are two of the most popular types of seams used by sewists everywhere.

However, we found that most people tend to confuse between these two seams.

We’ve, therefore, decided to come up with this post to teach what each seam is all about, what it looks like, and when to use them.

Let’s get into more details…

Flat Felled Seam

This is a type of seam that involves using a plain seam to sew the right and wrong sides together, and then tucking the edges into each other in such a way that they get locked in. It’s them sewn down again using another plain seam along the other side of the seam width.

As you can easily tell from this description, this type of seam will be a good way to hide and protect the raw edges from exposure. Plus, it leaves the seams looking as clean and tidy as possible.

Keep in mind that this is also the strongest type of seam, which makes it suitable for sewing heavy clothes that require extra security to hold them together (e.g. the side seams of jeans and pants). Points of stress and high-traffic areas also require some extra strength, so you should consider using a flat felled seam on such parts.

Here’s how to do a flat felled seam:

Creating a flat felled seam is nothing complicated. Just follow the directions below to create one:

1. With the right sides put together, sew a 5/8-inch seam from the raw edge

2. Then, trim down one side of the seam allowance to 1/4-inch

3. Now fold the 5/8-in seam allowance over & around the ¼-in. Make sure you fully enclose the latter allowance with the former.

4. Stitch as close to the folded edge as possible

That’s it! You’ve successfully made a flat felled seam. Pretty simple and fast, right?

French Seam

A French seam is visually flattening, both on the inside and outside of a garment. It’s a type of seam where you sew the wrong sides of fabric edges together and then tuck them between the right sides. And then sew them down again so that raw edges get tucked away.

The end result is clean-looking and finishes the right and wrong sides of the seam.

French seams usually find use in thin garments (sheer, delicate, and lightweight fabrics). They can also be used on garments that don’t have a lining, such as a shirt or a bag.

Quick NOTE: A French seam shouldn’t be confused with a mock French seam. While both teams look very similar, the process of creating each of them is quite different.

Here’s how to make a French seam:

Just like in the case of the flat felled seam, making a French seam is easy and straightforward. This is how to do it:

1. With the wrong sides put together, sew ¼-inch from the raw edge

2. Trim the seam allowance to 1/8-inch. Remember to press down.

3. Now turn the fabric so that the right sides come together to encase the seam you’ve trimmed in the previous step

4. Press down and sew a 3/8-inch away from the folded edge. And then press again.

5. That’s it! You’re done making a French seam.


That’s all you need to know about flat felled and French seams. From what we’ve seen in our discussion above, it’s crystal clear that these are two completely different seams, destined for different applications.

We hope that the above info will help you decide the right type of seam to use for your specific sewing projects.

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