Can't Zip Up? Here's How to Upsize a Dress in 4 Simple Steps

5 Materials
30 Minutes

In this tutorial, I'll show you how to upsize a dress quickly and easily.

Often, I find a dress at the thrift shop that I simply can’t ignore. The unfortunate reality is, it’s much too small for me.

However, the good news is there is a simple way to upsize a dress that won’t close, and I am going to show you how to do that today!

Follow along as I show you my thrift-flip technique for how to upsize a dress.

Tools and materials:

  • Dress
  • Matching fabric
  • Scissors
  • Pins
  • Sewing machine
The small dress before upsizing

Cutting the side seams of the dress

1. Cut the side seams of the dress

To begin, I cut the side seams, making sure I cut an equal amount on both sides of the dress.

Cutting fabric from an old t-shirt

2. Cut fabric from a t-shirt

Next, I cut a triangle of fabric from an old t-shirt. I used the sleeves of the t-shirt since the edge is already finished, which saved me a step.

The length of the triangle is equal to the length of the cut in the dress. The width should be 10-15 centimeters (4-6 inches), depending on how much extra fabric is needed to make the dress fit properly. 

How to upsize a dress using t-shirt fabric

3. Pin and sew

I turned my dress inside out. Then, I pinned the triangles into the slits I had cut on the sides of the dress, making sure the top edges were even with the armholes.

Next, I sewed them in place. 

Finishing the raw edges with a zigzag stitch

4. Zigzag stitch

To prevent fraying, I finished all the raw edges with a zigzag stitch. If you have a serger, you can serge the edges instead.

DIY upsized dress close up

DIY upsized dress

The dress fits now perfectly!

How to upsize a dress

How to upsize a dress

This technique can be used for all different types of clothing, not just dresses. The stretch in the t-shirt fabric is what makes this DIY the best solution!

Let me know what you think of this tutorial on how to upsize a dress in the comments below!

Suggested materials:
  • Dress
  • Matching fabric
  • Scissors
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