How to Make Bell Bottom Jeans or Flare Pants Sewing Tutorial

Read to make bell-bottoms or flare leg pants? In this sewing tutorial, we'll take an existing pair of jeans and quickly turn them into bell-bottom jeans! Here's what you will learn in this sewing tutorial:

1. How to modify your blue jeans to turn them into bell bottoms
2. Methods for ripping jeans seams efficiently
3. How to design your own sewing pattern you can use again and again

I've been teaching sewing and quilting online since 2009, but I made my first pair of bell bottoms using this method back in 1997 - the summer before 7th grade! 

This comprehensive bell bottom jeans sewing tutorial will guide you through creating pants with a flare. No matter if you're starting with skinny jeans or straight leg pants - you can turn any pair of denim jeans into bell-bottoms.

Note - this post includes affiliate links to useful supplies Amazon. This helps support this free sewing tutorial at no additional cost to you.

Here's a list of the materials I used to sew my flare leg pants. It's a lot easier to sew using jeans you already own and simply modifying the legs to flare beautifully. Make sure to follow the directions on the pant length to get the right bell-bottom effect!

Materials:

1. Sewing machine with basic sewing feet
2. Blue jeans that fit nicely in the hip and waist and are a bit long in the leg. 
3. Fabric to sew into the leg to create the bell-bottom effect. Cutting up another pair of jeans works great as you'll see in this tutorial!
4. Blue cotton sewing thread to match your jeans
5. Firm sewing pins
6. Fabric Markers
7. Microtip Glue Bottle (optional)
8. Sharp seam ripper
9. 18-inch Ruler
10. Soft sewing measuring tape
11. Large graph paper to create the sewing pattern
12. Contrasting white cotton sewing thread for decorative stitching.

Bell bottom pants—flared from the knee to a wide opening at the ankle—trace back to the early 1800s, when sailors in the U.S. and British navies wore loose, flared trousers. The practical wisdom of the day held that the wide legs were easier to roll up for deck work and simpler to remove over shoes, though how deliberate that design really was is a matter of some debate.

The style stayed nautical until the 1960s, when surplus naval trousers found their way into the counterculture wardrobe. By the late '60s and into the 1970s, bell bottoms had exploded into mainstream fashion, embraced by hippies, rock stars, and disco dancers alike, often in denim, corduroy, and bold prints.

They faded in the 1980s but have returned in waves ever since. I first made bell bottom pants this way in 1997. Back in middle school, I couldn't find the pants I wanted to wear in stores, so I modified the jeans I had on hand.

Since 2023, this tutorial has gotten a lot of attention as many women and men are searching for flare pants and bell bottoms again - proving that a good silhouette never really goes out of style.

Now we will draw our sewing pattern, yes, just using the two measurements we've taken! Click Here to find the best graph paper to help you make lots of sewing patterns.

When it comes to drawing this pattern, start by drawing a straight line and mark the height measurement we determined first. Next, draw a line perpendicular to the first. We want to mark the width of the flare shape, but center it over the height measurement.

Here's a diagram for how to draw your bell bottom sewing pattern on graph paper:

Now let's add seam allowance to our sewing pattern. We add additional fabric to the outer edges of the shape. This is the fabric added that we take away when we sew the seams. This seam allowance goes to the inside of the flare pants, so it's hidden once the seams are sewn.

But if this extra fabric is not added to the pattern to start with, your bell-bottom shape will be smaller than desired on all sides. It might even run so small it pulls awkwardly around the hem.

To add seam allowance, measure and mark additional lines 1/2-inch to the outside of the two angled lines.

The seam allowance added to the top point of your bell bottoms sewing pattern will end up much longer than needed. Measure 1-inch from the top point and draw a line perpendicular to the height line as shown below. This will create a blunted top to the triangle that will fit into your pants opening perfectly.

For the hem, add 2-inches to the bottom edge. It's always best to have more space to the top and bottom of this flare insert piece if you need it.

Why use a 1/2-inch Seam Allowance?

Many commercial sewing patterns use 5/8-inch seam allowance. If you're most comfortable sewing that way, make sure to add that amount to your sewing pattern.

I prefer 1/2-inch seam allowances for sewing patterns because it requires less fabric and is often easier to visualize using the edge of the presser foot as a guide.

You might have already jumped ahead on this step as I mentioned earlier you could go on ahead and rip the seams up to the point you marked for the bell bottom height. 

If you haven't already ripped the seams, let's discuss how to quickly and easily rip seams in blue jeans. Most jeans have a line of double stitching that run up the sides. This is a distinctive seaming style that we often take for granted, but trust me, after ripping out a few of these, you won't forget how jeans are made!

Start at the hem and using a sharp seam ripper with a tiny blade like this one, dig into the seam and begin ripping out the stitches. This is the hardest part and you have to be pretty aggressive.

Once you get past the hem, things will get a little easier. As you start to rip up the side seam, look at the stitching carefully. If you cut just right, you may be able to unravel the chain stitching. Just make sure to stop unraveling before you reach the spot you've pinned on the leg.

Carefully pull out or rip the stitches until you reach the point you've marked on the side seam. When I reached that point, I took the thread tails and tied them in an overhand knot and stitched back through the jean seam allowance a few times. This ensured the stitching would not continue to unravel.

Repeat this step for the other leg of your pants.

You can also rip the inside seam of your jeans too. This will double the size of your bell bottom pants, making them flare out significantly from the knee to the ground.

This new pair of bell-bottoms was stitched up a notch by adding curving lines of decorative stitches to the flare insert before cutting out the shape. Lacy first tested the designs on denim material using the Decorative Stitch Swatcher template.

This template allows you to preview nine designs in one small square, experiment with your decorative stitch settings, and determine if you need stabilizer behind your fabrics.

The great news about denim material - it's heavy enough that it doesn't need additional stabilizer to handle decorative stitches!

To create the special detail on my bell bottoms, I marked gently curving lines using the Mini Slide Ruler. Lacy followed the lines with different decorative stitches set to the standard stitch length and 4.0 mm wide. The biggest tip when using decorative stitches in your sewing machine is to go slow and allow the machine to feed the fabric forward. 

Just use your fingertips to steer and stay on the line and your decorative stitches will look great!

It's time for the exciting part of this sewing tutorial - cutting out our fabrics and getting ready to sew the pieces together. Follow these steps to modify your blue jeans to create funky flares or bell bottoms as big as you desire!

More prep? I know, this might seem silly, but the more time we take to secure the flare insert into the jeans and smooth out the fabrics, the easier this process will go.

These two steps will seem small, but will make a big difference in how easily the flare insert fits into your jeans.

1. Prep the Edges - Turn your jeans wrong side out and flatten out one leg over your pressing board. Check on the ripped edges of the jeans. One edge will naturally fold to the inside nicely. The other edge might need to be clipped free from the side to fold over. Press both denim edges so they are flat and crisply folded.

If the fabric feels very loose and wiggly, spray it with starch and press with a hot, dry iron. This will give the denim fabric more body and help you fold over the seam allowance with a nice, crisp fold.

2. Seam allowance check - This step is optional, but might clear confusion if you're a beginner sewist. The turned edge of the jeans will likely be wider than 1/2-inch on one side. If you wish to make this project easier, measure and mark a line with a fabric marker 1/2-inch from the folded edge of the jeans.

Carefully cut away the extra fabric from the seam allowance with sharp scissors. Doing this little step allows you to align the edges of the flare insert directly with the turned edge of the jeans. Less guess work means less fuss when sewing later!

We're finally ready to sew! We're going to stitch along the fold on the jeans to sew the pieces together.

First stitch from the pant hem up to the top of the flare with a 1/2-inch seam allowance, making sure to backstitch at the beginning and end of your seam.

Now for the second seam, which is a little harder than the first because it begins at the top and we stitch down to the hem. We have to stitch in this direction because of the way the seams are folded.

Because denim fabric is so prone to fraying, switch to a zigzag stitch and zigzag close to the stitching line. The settings I used on my Singer Heavy Duty sewing machine were 2.5 mm length and 4.0 mm width.

Using sharp scissors, trim away the extra denim fabric extending beyond the zigzag.

The bell bottom sewing tutorial video above was created in 2026. This sewing video is the original sewing tutorial made in 2016. The method is very much the same, but I made a few mistakes with this pair of bell-bottoms so it's good to see the process in a different light.

If you slip on your bell-bottoms and find they look weird (like the worst type of high-water pants you've ever seen) then they may be too short.

Bell-bottoms look best when the pants arch out from the knee or calves of your legs and fall to the ground to cover your feet completely.

To extend the length of your pants, slice off the hem and follow the instructions in the video to add a length of fabric. Make sure to follow the steps to angle the fabric join so the fabric extender also flares subtly out from the leg, following the angle created by the bell-bottom insert.

I added an additional 4 inch strip of fabric and sewed it to the bottom of the pants with a 1/2 inch seam allowance, then turned up the hem 3/8 inch.

We've stitched it up a notch today, my sewing friend! I hope you're excited to start sewing your own bell bottom pants. From this sewing tutorial, you've learned: