Easy Sewing Hack: How to Adjust the Waist on Pants

Enitan Agbabiaka
by Enitan Agbabiaka
8 Materials
1 Hour

I really like the fabric and style of these stretch pants. Unfortunately, they’re way too big for me on the waist and the crotch is too low and baggy.

I’m sure I can make them fit, so follow along and see how to adjust the waist on pants and then we’ll work on the crotch.

Tools and materials:

  • Stretch pants with elasticated waist
  • Seam ripper
  • Pins
  • Scissors
  • Hand sewing needle and thread
  • Fabric marker
  • Measuring tape
  • Sewing machine
Trying pants on

1. Try them on

Try your pants on and decide just how much they need to be taken in.

My pants were several inches too big around the waist, as well as being too long in the crotch.

Opening the waistband

2. Open the waistband

Turn your pants inside out.

Use a seam ripper to open approximately 1 inch (2.5 cm) of the seam on the inside of the waistband at the back.

Opening the waistband

Pull out a section of the elastic.

Shortening the elastic

3. Shorten the elastic

The waist of my pants needed to be 6 inches (16 cm) smaller in total.

Measure and mark half that amount - 3 inches (8 cm) in my case - along both edges of the double thickness of the elastic from the seam. 

Draw a line across the elastic joining both marks. This will be the new seam line.

Shortening the elastic

Place a pin in the elastic to hold the two thicknesses together.

Sew along the line you drew several times, with a straight stitch.

Shortening the elastic

Cut off the excess elastic, leaving approximately half an inch (1 cm) seam allowance.

Sewing the seam up

4. Sew up the seam

Push the elastic back inside the waistband.

Hand sew the folded edges of the seam together invisibly, using a ladder stitch.

Marking the crotch adjustment

5. Mark the crotch adjustment

Try on the pants again with the smaller waist and decide how much shorter the crotch needs to be.

I’m reducing mine by half an inch (1 cm) front and back.

Take the pants off and turn them inside out with the front facing you.

Align the crotch and inner leg seams.

Marking the crotch adjustment

Measure and mark half an inch (1 cm) from the inner leg seam either side of the center front seam of the pants.

Marking the crotch adjustment

Measure and mark 4 1/2” (11 cm) from the center seam down each inner leg seam.

Marking the crotch adjustment

Join the side marks to the center with a tapered line.

Shortening the crotch seam

6. Shorten the crotch seam

Pin the front and back crotch seams together to make sure they’re aligned.

Shortening the crotch seam

Sew along the tapered line twice, with a straight stitch set to length 2.

Trim the excess fabric in the center.

Shortening the crotch seam

Set your machine for a zigzag stitch of width 3 and length 2.

Sew along the raw edges you just cut, to stop them from fraying.

How to adjust the waist on pants

How to adjust the waist on pants

And now I have a pair of stretch pants that fit perfectly around the waist and crotch!

It’s a really quick and easy job to do yourself and it makes a huge difference in the fit.

I hope you enjoyed watching how to alter trousers at the waist and that you’ll feel confident to do it yourself.

Please let me know what you think in the comments below - I love to hear from you.

Next, check out my Easy High-waist Pants Sewing Pattern Tutorial.

Suggested materials:
  • Stretch pants with elasticated waist
  • Seam ripper
  • Pins
See all materials

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