How to Sew French Seams for Beginners

One of the simplest ways to transform your garments from feeling homemade to looking professionally-made is by using French seams.

Instead of a simple side seam that most patterns use, French seams have you enclose the fabric's raw edges within the seam allowance.

This gives your garments a clean finish that works great for any piece, but especially well for business casual or formal wear.

This tutorial will show you how to sew French seams on a Riviera Shirt. However, you can use this for any pattern you have. 

Step-by-Step French Seam Tutorial

Before you begin, make sure to give yourself at least ⅝" for seam allowance. Remember that French seams require a little extra seam allowance since you're going to fold the edge over itself.

If you'd like to use a French seam for shirts like the Riviera, we recommend first-timers French-seam the side seams, then a standard seam for the sleeves. This is because using French seams for sleeves can be quite complicated.

That said, once your pattern and fabric are ready, here's how to proceed: 

Step 1: Prepare Your Fabric

Unlike most other seams, you start sewing a French seam with the wrong sides of the fabric facing each other, and the right sides of the fabric facing out.

Once you have your fabric in place, use pins to hold the pieces together. Place your pins perpendicular to the seam line. This way, they're easy to remove, and you can even sew over them if need be. 

Step 2: Sew The First Seam

Next, sew your first seam, which is a basic side seam.

Give yourself ⅜" of allowance for this first seam. You can start by sewing a simple backstitch to prevent unraveling, then slowly sew the entire side.

To keep your stitch straight and even, use the needle plate marker to measure ⅜" all along your stitch. If your needle plate doesn't have markings, use a ruler and chalk to mark where the seam should go. 

Step 3: Trimming the Seam 

Once you're finished with your first seam, use your iron to press the seam allowance to one side.

Then, take your fabric scissors and trim the seam allowance as close to the seam as you can. You want the seam allowance to be as small as possible, about 1/16".

This edge will be hidden in the final seam, so you don't need to stress about making it perfectly straight. However, be careful not to cut the seam. 

Step 4: Pressing the Seam 

After cutting, use your finger to split the edges of the seam allowance, then press them open. You can use your iron to press, or you can simply press the edges down with your finger.

Pressing the seam open creates what we like to call a "crisp ditch." It might seem like a small detail, but it will give your finished seam a much cleaner and more professional look. 

Step 5: Fold and Pin The Second Seam

With the crisp ditch in place, fold your fabric so that the right sides are facing each other, and the wrong sides are facing out.

Push the seam outwards so that the fold is right on the seam line. You can also press the seam so it stays flat.

Then, pin your seam in place so it doesn't open up as you sew. 

Step 6: Sew the Second Seam

Finally, take your sewing machine and sew a second seam with ¼" of allowance. When you're finished, press the fabric one more time, and you should have a clean, professional-looking seam.

Step 7: Sew the Sleeves In

For first-timers, we generally recommend using a French seam for the sides and using a standard seam for the sleeves. This is because using French seams on sleeves is quite complicated.

However, if you're up for the challenge, here's a video demonstrating how it's done: 

Troubleshooting Common French Seam Issues

Raw Edges Showing Through

 If you've just finished sewing your French seam, but the raw edge of the first seam is peaking through the fold, you may have sewn the second seam too close to the edge.

An easy fix for this is to sew another line next to the seam you did to close the raw edge in.

To avoid this happening in the first place, follow the measurements carefully. This shouldn't happen if you trim the first seam edge to 1/16" and give the second seam at least ¼" allowance. 

Finished Piece is Too Small

Another problem many first-timers run into is their finished piece being too small for them once they're finished. This can happen because most patterns are measured for a simple side seam, while French seams need more allowance.

Unfortunately, if you run into this problem, you may need to adjust your pattern and cut a new piece of fabric.

That's why, before cutting your fabric, always give yourself at least ⅝" of seam allowance for your French seam. Some patterns only call for ½" of seam allowance, so adjust accordingly so you can use a French seam. 

Bulky Seams

Bulky seams are another common problem that can lead to an unprofessional look. Bulky seams can be caused by excess seam allowance, uneven cutting, or not being pressed.

• For excess seam allowance, make sure to cut the allowance of your first seam as close to the stitch as you can. Aim for 1/16" if you can, but be careful to avoid cutting the stitch.

• While cutting the excess, do so in smooth, even cuts. It doesn't have to be perfectly straight, but an obvious uneven cut can create bulky seams.

• Finally, press your fabric after every step with your iron. This flattens the fabric and prevents bulky seams once finished. 

Seams on the Wrong Side

Always remember: you sew the first seam with the right side facing out. One of the most common mistakes we see first-timers making is sewing the first seam with the wrong side out.

It's a very common mistake to make because wrong-side out is how you sew most other seams. However, in the case of French seams, always remember that it's right side out. 

Elevate Your Sewing with French Seams

Learning how to sew French seams will give your clothes a noticeable professional touch. You won't feel like you're wearing something homemade, but something made by an experienced tailor.

So next time you're working on a pattern, give yourself a bit more seam allowance and try a French seam.

If you're not sure which pattern to try this on, French seams go perfectly on business casual or more formal wear, such as the Riviera shirt. 

If you'd like to have a go at it, you can grab the Riviera shirt pattern below!