How to Shrink Polyester and Spandex Clothing

If you have a polyester or polyester and spandex garment that is just a little too big, this article will explain everything you need to know about how to shrink any kind of polyester clothing. We also dive into how to shrink polyester-spandex and polyester-cotton blends.

Let’s start with the most important question…

Can You Shrink Polyester?

Well, it’s not easy…

Polyester is actually far more resistant to shrinking than natural fibers like cotton and wool. For example: Shrinking 50% cotton-polyester blends is much easier than 100% polyester.

That being said, it should be possible to shrink any polyester garment by a tiny amount. The key is to use excessive heat. What you’re actually doing is “melting” the polyester fibers ever so slightly, causing them to reduce in length.

The natural fibers like cotton will seek to return to their slightly “coiled up” state, assisting in the overall shrinking. Depending on the blend amount, you should be able to reduce the size of the garment between 1 and 3 sizes.

Spandex is another synthetic fabric that is highly resistant to shrinking. Polyester-Spandex Blends are therefore the least likely to shrink, but with the right steps, it might just be possible.

How to Shrink Polyester Clothes

The following steps will show you how to shrink both polyester clothes as well as polyester-spandex blends. You may repeat any of the steps at any point to advance the shrinking further.

A WORD OF WARNING: Shrinking polyester clothing is not a science. There’s no way to know exactly how the garment will react or whether the shrinking will even be consistent across the entire garment. We suggest that you only attempt this if you are absolutely sure that you will no longer be wearing the garment in its current state and it would have been otherwise discarded.

1. Wash on High Heat

Set your washing machine to its highest heat setting and wash the garment or fabric.

Here are the approx. normal washing temperature settings for fabric (which shouldn’t result in shrinking):

  • Wool and Silk: 85°F | 30°C
  • Cotton and Polyester: 105°F | 40°C
  • Polyester-Cotton Blends: 120°F | 50°C

If you want to purposely shrink 100% Polyester or Polyester-Cotton blends, you could set the heat to between 140°F and 190°F | 60°C and 90°C

At the most extreme settings, you should definitely see a difference in the size, especially if you’re working with 65% cotton and 35% polyester blends, but proceed with caution as it might also irreparably damage the garment.

The more synthetic blends like Polyester-spandex will require the highest possible setting to show any shrinking.

2. Dry on High Heat

For the best results, tumble dry the garment immediately after it comes out of the washing machine.

Your dryer should have a couple of settings, ranging from Delicate to Heavy-duty. Here are the average approximate heat settings:

  • Delicate: 125°F | 50°C
  • Medium: 135°F | 60°C
  • Heavy-duty: 135°F | 60°C (but with higher agitation)

Heavy duty is usually the hottest heat setting possible and also uses the most agitation to dry the clothes. It’s designed for the heaviest linens and works the fastest but also has the highest chance of shrinking your clothes.

If your dryer goes even higher, you may want to give it a try.

3. Ironing on High Heat

Here is where you have to be really careful of irreparably damaging your polyester clothing.

The hot soleplate of the iron can reach up to 400°F | 200°C

This is very near the melting point of polyester at 480°F | 250°C

And spandex 460°F | 240°C

If you use too much direct heat on the polyester, thinly woven fibers will easily melt together and cause “shine” marks or completely melted areas.

For this reason, we normally use a heat setting of 300°F | 150°C when ironing polyester.

This coincides with the medium heat setting, sometimes shown as 2 ironing dots on the laundry tag.

If you want to increase the chance of shrinking the garment, you may want to turn the iron up to High heat or 3 dots which should be 390°F | 200°C. There’s still a big risk that you damage the garment so you should absolutely place a protective cloth between the iron and the polyester clothing.

Steam will help the heat penetrate the fabric and increase the chance of shrinking. Just keep checking the garment for any visible damage and try inconspicuous areas first to be sure.

4. Shrink the Polyester in Boiling Water

Up until now, you’ve stayed under the boiling temperature of water 212°F | 100°C (other than using the steam from the iron)

By submerging the polyester or polyester-spandex blend in boiling water, you’re attempting a last-ditch effort to shrink the clothing. If this doesn’t work, nothing will.

You could even shrink the polyester without washing by jumping straight to this step.

Keep topping up the boiling water regularly and keep the garment submerged for around half an hour. Place a heavy item on the garment to avoid any parts floating to the surface and possibly being shrunk unevenly.

Once this is complete, allow the item to dry or repeat steps 2 and 3 if needed.

5. Conclusion

You should only use these techniques if you’re OK to risk damaging the garment. You could always give it to someone smaller or have it tailored instead.

Any of the steps can be repeated or even left out if you feel they’re too risky.

How to Shrink 95% Polyester 5% Spandex

Follow the steps outlined above. Both Polyester and Spandex are highly resistant to heat and shrinking. Spandex is probably even more so.

It will be difficult, but not impossible. You can repeat the steps a few times and see which works better.

Perhaps consider skipping the ironing since spandex is even more likely to melt due to the high temperature of the soleplate.

Which Other Polyester Clothing Items can be Shrunk

The steps above will work on anything made of polyester or polyester blends.

It shows you how to shrink a polyester and spandex skirt as well as shirts, hoodies, jackets, shorts, and even polyester jerseys.

Since polyester-spandex blends are usually used in gym clothing, this method will also apply to most fitness wear.

Pay close attention to the fabric blends and in particular, how certain garments are made.

Quite often, there is polyester paneling on the inside of jackets and pants pockets, even if the entire garment isn’t 100% polyester.