Does Polyester Shrink?

Polyester is one of the most common man-made materials around and makes up a large percentage of synthetic clothing. We use polyester because it is cheap, durable, and easy to use in a range of garments. There is the assumption sometimes that polyester clothing doesn’t shrink – at least not in the same way as other materials. Is this the case? Will polyester shrink and, if so, what do you need to watch out for?

Does It Shrink?

The short answer here is that polyester can shrink under certain conditions. Extreme temperatures can affect the fibers and cause them to shrink down. However, the good news is that polyester is unlikely to shrink in a regular wash or a gentle setting in a dryer.

Therefore, you shouldn’t experience any issue with polyester clothes fitting unless there has been a mistake drying the garment on a high temperature setting. This slight shrinkage capable in extreme temperatures also means that you could potentially shrink an oversized garment.

How Much Does Polyester Shrink?

100% polyester doesn’t actually shrink that much because it is quite a tough and resistant fabric. So, you will need some extreme methods if you have a 100% polyester item of clothing. It is much easier if you have a blend with a natural fiber, such as cotton or linen. Check the care label on your garment for a better idea of what to expect. You can then tailor your process accordingly.

Can You Deliberately Shrink A Polyester Item To Make It Fit?

There will be times where you want polyester clothing to be able to shrink. You may have found an old shirt that is a little too large or found something cool in a thrift store. With the right control over washing and heating your garment, you might be able to shrink it a little. You just need to be aware of the process and the composition of the item.

Also, be aware that you might not get the fit you want this way. Excessive ironing in all the right places isn’t going to tuck in a shirt to fit your waist. There is always a risk with this process and you have to consider how prepared you are for it to go wrong.

Will Polyester Shrink In The Wash?

There are few risks of polyester shrinking in the wash on accident. The fibers are robust enough that a simple 30-40 degree Celsius wash won’t do any harm. Higher temperatures are more problematic. It is still a good idea to pay attention to settings and to make sure that the garment doesn’t sit in the water for too long.

Instead, the washing machine is a good place to start when deliberately shrinking polyester clothing. This is because of the temperature controls and the fact that wet fibers are easily manipulated. But, it is also just the start of the process. You should be able to soak the garment at high heat for a long time with greater ease than soaking it in a tub or basin.

Don’t worry about detergent and treating this too much like laundry. The main aim here is simply to soak and then dry out the polyester fibers. It might help to turn the item inside out to protect any print and dye from damage. If this does happen thought and part of the print comes off, check out our guide on how to remove the entire screen printing from the shirt here.

Will Polyester Shrink In The Dryer?

There is a greater risk of shrinkage in the dryer because of the high heat and the way the drying process affects the sodden fibers in the clothing. Again, the higher the heat, the greater the risk. There shouldn’t be a problem on a normal cycle but you could air-dry clothes if you are concerned.

If you are deliberately shrinking polyester then it is a good idea to put the wet item in the dryer at as high a heat as possible. You might not be able to reach the optimal levels, but it is easier than any other way of heating clothing. Don’t have too high an expectation of the outcome because you could see anything from a significant alteration to no change at all.

What Temperature Do You Need For Polyester To Shrink?

There are different opinions on the best temperature to use. This can depend on the method, material blend, and how much shrinkage you need. How hot is hot enough? Hotter than you might expect. The average range for heat to take effect on polyester is 155 – 178F or 68 – 81C, depending on which you prefer to work with. This could be an issue when deliberately shrinking polyester with a washing machine as they may not have a cycle that goes this high. On the flip side of this, it is very unlikely that a basic cycle will do any harm.

Will An Iron Shrink Polyester?

There are those that will use an iron to help speed up the process and apply heat. This isn’t a terrible idea when you have control over the settings and pay attention. Direct heat on the fabric can shrink the fibers better than some high-heat settings in a dryer. However, there is the risk that you will target specific areas too much, whereas a dryer provides consistent heat to the entire garment evenly. Also, you need to be careful not to burn the fabric by leaving the plate on there too long.

It is always recommendable to use a pressing cloth when ironing to avoid damage. This is especially important for polyester items you want to protect. But, don’t neglect this when shrinking polyester on purpose either.

How To Shrink Polyester With An Iron

There is a good chance that this approach with the washer/dryer won’t be enough to get the level of shrinkage you expect. An alternative option here is to put the wet garment on an ironing board and use the hot plate of the iron for more direct heat transfer. Don’t use the steam setting because you just want to dry out the fabric. Use a pressing cloth for protection. At this point, you have probably stretched it as far as it will go.

How To Shrink Polyester In Boiling Water

This next option is a bit drastic and more dangerous. But, it could work in extreme cases. If the washing machine doesn’t get hot enough, you may need to boil some water and use that instead. This is where you can get those temperatures closer to 170 degrees F. Use a thermometer to keep an eye on the water temperature before adding your material. The shock of the hot water should cause a greater reaction in the fibers for a more noticeable change in shape. The downside here is the safety issue of the hot water, so be sure to wear gloves and use tongs when handling the fabric.

Do Polyester Blends Shrink More Easily Than 100% Polyester Items?

Finally, it is important to consider the ratio of the composition of a piece of clothing. There is a good chance that your favorite shirt isn’t 100% polyester, and is in fact only 75% or even 50% polyester. The rest may be cotton, which is far more prone to shrinkage. Therefore, it will take less effort and lower heat for these items to shrink. This is great when deliberately shrinking items to fit, but you have to be careful with more prized pieces. This is a good lesson in why we all need to read clothing labels when buying clothes.


In short, you shouldn’t assume that you can do anything to a 100% polyester item and it will retain its shape. Excess heat from a dryer or iron could cause a little shrinkage. This is fine if you need to alter the fit of a garment, but a problem otherwise. Also, don’t forget that shrinkage is more likely with polyester blends. So, always check the labels on your clothes and take good care of them to avoid unwanted shrinkage.