If you have a polyester shirt that you would love a whole lot more if it was just a little bit smaller, there may be a solution for you. Although you will hear that polyester clothes cannot be shrunk, this can be incorrect if you know what you are doing. Because polyester is a synthetic fabric, it will not shrink much, but you can get something to fit you a little bit better.
The most important thing for shrinking polyester is heat; and if you look at the washing instructions on your polyester clothes, you will find that they tell you to wash in cold water and to dry on a low temperature. In order to shrink these polyester clothes a little bit, these washing instructions must be ignored!
For all polyester clothing items (not just shirts, but pants and anything else!), the first thing you want to do before trying to shrink them is turn them inside out. As your clothes go through the heat of the washer and dryer, the colors will be protected if they are inside out. Unless you have a “boil wash” setting on your washer (which can cause polyester to harden), you will want to wash these clothes on the hottest temperature. You do not need detergent for this; you simply need to get your polyester clothes into that hot water for a fair amount of time.
Immediately transfer the clothes to the dryer when they are finished washing, and run the dryer on the hottest setting. If the clothes are still damp when you take them out of the dryer, you will not achieve the desired results; make sure the clothes are completely dry before you remove them. Lastly, try the clothes on and see if they have tightened up as much as you would like them to. If the clothes are not quite to the right size, you may have to repeat this process a couple extra times.
Although you will not be able to shrink polyester in the same way cotton or wool can shrink, you can certainly shrink it to a better fit if you take the right steps!