Easy Sewing Hack: How to Adjust the Waist on Pants

Tools and materials:

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

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.

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.

Pull out a section of 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.

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

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

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

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.

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.

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

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

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

6. Shorten the crotch seam

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

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

Trim the excess fabric in the center.

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

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.