How to alter the waistband of kids' jeans (without darts!)

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My 12-year-old daughter has grown a crazy amount this year. She’s always been tall for her age and I expect her to outgrow me by the end of the year (I’m 5’6”, but I’m pretty sure I’ll end up the shortest in my family). Last Sunday she was lamenting that she didn’t have anything to wear. I went in to help her and realized she was kinda right, ha! She’d outgrown pretty much everything. So we went shopping!

We started at Savers (our favorite thrift store) and found a nice haul including three pair of jeans. One pair was Madewell and we got them for $5!!!! I love it when the thrift store doesn’t recognize an expensive brand, haha. The other two are super cute, but slightly big in the waist. She doesn’t love belts, so I said I’d alter them.

I didn’t want to do darts because once that’s done, it’s done and I wanted a less permanent solution so we can take it out if she needs. I came up with a way to add an elastic casing in the back and thought I’d put the tutorial here.

How to fix a too-big waistband on your kids’ jeans, with no darts. || Pin, Cut, Sew Studio

All you need is a strip of fabric, 2” x 12” and a scrap of 3/4” or 1” elastic, about 6-10” long.

The first thing you need to do is remove the back belt loop with your seam ripper. I removed mine completely, but if you want to keep the belt loop, simply unpick the top of it and keep it out of the way while you sew, then top stitch it back in place at the end. This will be challenging unless you have a pretty heavy duty machine. I don’t like to risk putting my eye out with a broken needle, so I left them off.

How to make a jeans waistband smaller. || Pin, Cut, Sew Studio

Next, take your 2x12” strip of fabric and hem the short ends. Then, press under the long ends, 1/4”.

How to alter a jeans waistband, without darts. || PIn, Cut, Sew Studio

Pin your strips onto the inside of your waistband, centered over the center back seam and edge stitch them on, both long edges, leaving the short ends open.

How How to alter the waistband of jeans

Take your strip of elastic and attach a safety pin to one end. Thread it through and once it gets to the end of your casing, stitch that end down. At this point, I had Layla try on the jeans and pulled the elastic so they fit how she wanted. Then I stitched the other end in place and trimmed the excess.

How to add elastic to kids jeans.
How to alter the waistband of jeans. No darts! || PIn, Cut, Sew Studio.

If you want a less gathered look in the back, you could remove all three of the back belt loops and make your case go from side seam to side seam. Layla doesn’t mind the gathers, she likes the cute fabrics and they look great when she wears them. This pair is a cute Jennifer Lopez brand boyfriend jean (anyone else watch World of Dance? The girls and I love that show!)

How to add an elastic casing to too big jeans. || PIn, Cut, Sew Studio

I hope this helps some of you! I have used a similar method to fix a case of shot elastic when my son was very young. I just added an extra casing all the way around the inside and put new elastic in that way. If you have other ideas for simple alterations of pants, let me know!