How to Shrink a Polyester Hat: The 3 Best Methods

Is your favorite baseball cap feeling a little too loose? Whether it's been stretched out through everyday wear or it's always been too big (but you love it anyway), there's no reason to let it go. With a little know-how, you can easily size down your hat for the perfect fit.

To begin, you must determine the hat's material. If it's made of cotton that is not preshrunk, the natural cotton fibers will easily shrink in the washing machine and dryer, even in low heat. You could also wash baseball hats by hand. The same goes for wool hats, just exercise extra precaution since wool is prone to losing its shape. Take a look at our guide on the best ways to shrink a wool hat to make sure you do it right.

Likewise, if you have a polyester hat, putting it in the washing machine and dryer can shrink it. That said, unlike cotton and other natural fibers, polyester is a synthetic material that can be more resistant to shrinking. As such, the key to shrinking a polyester baseball cap is heat — that means hot water and hot air. Read on for step-by-step instructions to shrink a polyester hat and then decide which method is best for you.

Washing Machine Method

For those who are short on time (or patience), the washing machine method works best.

1. Put the cap in a garment bag.

Even though polyester caps are quite durable, they can still get shredded or misshapen in your washing machine. To minimize the chances of ruining the hat, place it in a garment bag before washing.

2. Load the hat with similarly colored clothes.

Washing the cap with a load of laundry is a good idea for two reasons: It doesn't waste water and the other clothes create pressure to speed up the shrinking process. Use the recommended amount of non-bleach laundry detergent depending on load size.

3. Use the hot water setting.

You could use warm water instead, but if your hat needs to shrink a half-size or more it's best to use high heat.

4. Try on the cap once it's finished washing.

If the hat still feels too loose, it's time to throw it in the dryer. (Proceed to step 5 below.) If it feels a bit snug, wear it for a while and let it air dry to allow the fibers to stretch and conform to your head.

5. Put the hat in the dryer for further shrinkage.

Use a medium heat setting. High temperatures are required to shrink a polyester hat, but if they are too high, your hat might end up frayed, scorched, or otherwise ruined. Check on the hat every 10 minutes or so to make sure it's OK and try it on. Once the cap gets to the size you want, you're all set.

Hand-Wash Method

Washing a synthetic cap by hand is a more gentle and ideal approach if you don't need the hat to shrink that much.

1. Fill a pot or sink with hot water.

Make sure it's not boiling water as this will ruin the hat's structure. If you are heating a pot of water on the stove, it should be steaming not boiling.

2. Add a tablespoon of non-bleach detergent.

Mix in the detergent and stir it around in the hot water. You could also use dish soap.

3. Dunk the hat in the soapy water.

You can try this with your bare hands, but it's best to use a pair of kitchen tongs since you're dealing with extremely hot water.

4. Let the cap soak for at least 30 minutes.

Depending on the hat's percentage of polyester, the hot water will begin to shrink the fibers at varying rates.

5. Rinse off the wet hat.

Remove any suds with warm running water, then gently dab away the excess water with a clean towel.

6. Put on the damp hat and let it air dry.

This will take a while, but as the hat dries it will conform to the shape of your head. If you want to speed up the shrinking process, move on to the next step.

7. Use a hair dryer for further shrinkage.

Even though high heat is the key to shrinking a polyester hat, use the blow dryer's medium heat setting to avoid any potential problems. You can either hold the hat while blow-drying it or wear it on your head as you apply heat so that it dries to the shape of your head.

Shower Method


How to Shrink a Polyester Hat: The 3 Best Methods - Shower method

Everyone loves a hot shower and this method for shrinking a polyester hat gives a whole new twist to the term "shower cap."

1. Get ready to take a shower.

Obviously, you don't need any instruction for taking a shower — just make sure you wear the cap you want to shrink.

2. Shower as usual and let the hat get soaked.

Allow at least five minutes to completely soak the crown. You can gently wash the hat while showering but it's not necessary.

3. Rinse off.

Once you're done showering and dried off, make sure to dab the cap so that it's no longer dripping wet.

4. Wear the hat and let it air dry.

The best way to achieve a perfectly fitted baseball cap is to let it dry while wearing it. Sure, it might take all day, but it's worth the wait. If this isn't an option, you can always use a hair dryer to speed up the process. Or you could throw it in the dryer as long as you check on it every 10 minutes or so.

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How to Shrink a Polyester Hat: The 3 Best Methods

As you can see, there's no polyester hat that's too big to fail. Whether it's throwing it in the washing machine, tending to it by hand, or simply taking a shower with it, all you really need is some heat and a few simple steps to shrink your cap into shape. Once you have the perfect fit, you'll want to make sure you're wearing it properly, so be sure to check out our list of do's and don'ts of wearing a baseball hat.


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