How to Wash and Care for a Baseball Cap

Tips to keep caps clean, stain free, and proper storage for collectibles

Baseball caps hanging from a hook

The Spruce / Fiona Campbell 

Project Overview
  • Working Time: 20 - 45 mins
  • Total Time: 1 day
  • Skill Level: Beginner
  • Estimated Cost: $0 to $10

Proper cleaning methods for baseball caps vary depending on your hat type. Most manufactured baseball caps are now typically made of cotton twill, cotton-polyester blends, or jersey mesh, including a plastic form to shape the brim. These fabrics are strong, durable, and usually colorfast, so newer hats can be washed with cold water in a washing machine without becoming deformed.

Never machine-wash older caps with paper or cardboard brims, wool caps, or vintage baseball hats. All baseball caps should be air-dried rather than using a clothes dryer, which can shrink or misshape the material.

Follow these steps for washing, repairing, shaping, and storing any baseball cap to keep it looking its best.

What You'll Need

Equipment / Tools

  • Washing machine
  • Soft-bristled brush
  • Hat form (optional)
  • Towel (optional)
  • White cloth

Materials

  • Heavy-duty detergent
  • Oxygen bleach (optional)
  • Stain remover (optional)
  • Wool wash detergent (where needed)

Instructions

Materials for cleaning baseball caps
The Spruce / Fiona Campbell
How to Wash Baseball Caps
Detergent Heavy-duty (except for wool caps)
Water Temperature Cold
Cycle Type Delicate
Dryer Cycle Type Do not use dryer
Special Treatments Pretreat stains
Iron Settings Do not iron
How Often to Wash Every few months; or when visibly soiled

How to Wash Cotton, Polyester, or Mesh Baseball Caps

  1. Pretreat Stains

    Pretreat exceptionally dirty areas like sweatbands with a solvent-based or gel-type stain remover on new cotton, polyester, or mesh hats. You can also use a dab of heavy-duty laundry detergent such as Persil or Tide, which have a high concentration of enzymes to break apart soil, oil molecules, and perspiration stains.

    • Work the stain remover or detergent into the soiled areas using a soft-bristled brush.
    • Allow it to work for at least 15 minutes before washing. This pretreatment helps remove perspiration stains.
    Someone using a soft bristled brush to pretreat a cap
    The Spruce / Fiona Campbell 
  2. Presoak to Brighten Colors

    Mix a solution of oxygen bleach and warm water following the package directions if the cap looks dull and you want to whiten or brighten the colors.

    • Completely submerge the hat.
    • Allow it to soak for at least four hours or overnight.

    Warning

    Don't use chlorine bleach on your baseball caps or colorful accessories, even when treating a white hat. It can damage the polyester fibers and cause premature yellowing or discoloration.

    Someone pre-soaking a baseball cap
    The Spruce / Fiona Campbell 
  3. Add the Hat to the Wash

    • Remove your hat from the soaking solution.
    • Wash it without any other items, using heavy-duty detergent. Choose your machine's delicate cycle in cool water.
    • If you're concerned about protecting the shape of the cap, you can use a hat form to protect it in the wash.
    A baseball cap sitting on a pile of laundry in a basket
    The Spruce / Fiona Campbell
  4. Shape and Air-Dry

    Allow the cap to air-dry after washing in the washing form, over a large coffee can, or over another head-shaped container or form. Don't put baseball hats in the dryer: The heat and tumbling action can distort its shape.

    A baseball cap drying on a vase
    The Spruce / Fiona Campbell

How to Wash Baseball Caps With Paper Brims

Many hats made before the 1980s have paper-based cardboard bills. If the cap has a cardboard or paper-stiffened bill, spot-cleaning is the only method that won't damage the hat.

  1. Scrub Stains

    • Use a soft-bristled brush to lightly scrub the stained areas with a heavy-duty detergent and water mixture.
    • Add 1 teaspoon of detergent per 1 cup warm water.
    • Use the solution sparingly as you scrub to avoid getting the hat's brim too wet.
    Soft-bristled brush lightly scrubbing white cardboard brimmed hat

    The Spruce / Almar Creative

  2. Blot to Rinse

    Blot the area with a clean, white cloth dipped in water to rinse any remaining detergent.

    Clean cloth blotting white brimmed hat to rinse

    The Spruce / Almar Creative

  3. Air-Dry

    • Allow the cap to air-dry.
    • You may need to repeat the steps several times to remove all the soil.
    White cardboard brimmed hat air drying on wooden surface

    The Spruce / Almar Creative

How to Wash Wool Baseball Caps

Wool baseball caps should be hand-washed using cool water and a mild detergent intended for wool.

  1. Gently Wash

    Massage the soapy water into the hat gently; be sure not to scrub or twist the fibers.

    Wool hat gently washed with soapy water

    The Spruce / Almar Creative

  2. Rinse Thoroughly

    • Rinse the hat well in cool water.
    • Press it gently with a thick towel to absorb most of the moisture.
    Thick towel gently pressed on wool hat to rinse

    The Spruce / Almar Creative

  3. Shape and Air-Dry

    • Allow the hat to air-dry on a head-shaped object.
    • If you wear your wool hat while it dries, it should conform to the precise shape of your head.
    Wool hat air drying on head-shaped object

    The Spruce / Almar Creative

How to Wash Vintage or Commemorative Baseball Caps

If your vintage hat needs a deeper cleaning, before washing, do a colorfastness test.

  1. Test for Colorfastness

    • Using a damp white cloth, gently rub an inconspicuous area of the cap.
    • If there's color transfer onto the cloth, don't proceed.
    Damp cloth testing colorfastness on vintage baseball cap

    The Spruce / Almar Creative

  2. Mix the Cleaning Solution

    Mix a solution of 1 teaspoon liquid dishwashing detergent with 1 cup of warm water if the fabric is colorfast.

    Dishwashing liquid and water mixed for cleaning solution

    The Spruce / Almar Creative

  3. Wipe Down the Hat

    • Dip the cleaning cloth in the solution and wring it thoroughly.
    • Gently wipe down all surfaces of the hat.
    • Don't immerse your hat in the water; the cardboard in the brim will likely dissolve.
    White cloth dipped in cleaning solution to clean vintage baseball cap

    The Spruce / Almar Creative

  4. Rinse Well

    Use another cloth dipped in clean water to "rinse" the cap by wiping away any cleaning solution.

    White cloth rinsing vintage baseball cap with clean water

    The Spruce / Almar Creative

  5. Air-Dry the Hat

    Air-dry the cap away from direct sunlight; the time to dry can range from a few hours to overnight.

    Vintage baseball cap resting on wooden surface to air dry

    The Spruce / Almar Creative

How Often to Wash Baseball Caps

If you wear your hat frequently, a thorough cleaning every few months can keep it looking fresh. Before you start, read the hat's interior fiber content tag, including the manufacturer's cleaning instructions. Unfortunately, caps made before 1983 didn't require a label, so you may need to do some research about an older hat to confirm the care information.

Treating Stains on Baseball Caps

If you have stubborn perspiration stains, try a little bit of gentle hair shampoo, like baby shampoo. Rub a drop of shampoo and water into the stained area with a soft toothbrush. Be careful when using a toothbrush around threads, seams, and stitching so you don't dislodge the threads. Then, continue with the washing instructions pertaining to your hat type.

Soft toothbrush gently removing stain on baseball cap brim with shampoo

The Spruce / Almar Creative

Baseball Cap Care and Repairs

If the frayed edges on the bill are a problem, you can repair it with glue, but the hat will never look the same. Adding glue will also significantly change the value of a commemorative cap.

To temporarily stabilize the fraying, apply a small amount of school glue to the edges, gently pressing the fabric to lay flat. However, since the glue is water-soluble, it may discolor the fabric, and the glue will wash out the next time the hat is cleaned.

If a stub breaks on a plastic hat adjuster, replace the stubs completely by using super glue to add Velcro strips on the adjuster to create a new closure. For rips or more serious defects, a tailor or hat restoration service might be able to save a vintage or commemorative cap.

Baseball hat brim being repaired with glue

The Spruce / Almar Creative

Storing Baseball Caps

Commemorative caps should always be stored in a covered case to prevent dust and grease from accumulating. These should only need a light dusting or brushing yearly to keep them clean. If you have an autograph that you want to preserve, keep the cap in a dark, air-conditioned space to prevent fading and stop mold or mildew from forming.

All other hats can be packed in a plastic or cotton storage bin or stacked inside a cotton bag or pillowcase in your closet. If using a bag, ensure nothing compresses the hat, as this will change its shape. Always store baseball caps away from direct sunlight, heat, and moisture.

Wool and vintage baseball caps stored in plastic bin

The Spruce / Almar Creative

Tips for Washing Baseball Caps

  • Don't wash your cap in the dishwasher—detergents are too harsh and often contain bleach that can ruin the fabric. Additionally, the high drying temperatures can cause the fabric to shrink.
  • Don't put your cap in the general laundry because any agitation or friction with other items while washing can ruin the hat's shape.
  • If you want to wear an autographed cap, protect the signature by setting the ink. Cover the signature with a white pressing cloth, and iron with high heat to set the ink.
FAQ
  • How can I tell if the brim of my baseball cap is made of cardboard?

    If the brim of your cap bends easily and has a hollow sound when you tap on it, it is likely made of cardboard and should not be machine-washed.

  • Does this washing method work for any type of brimmed cap?

    Yes. Most promotional or souvenir caps are constructed the same way as baseball caps and can be washed the same way.

  • How can I brighten a white baseball cap without bleach?

    Chlorine bleach can break down the fibers of baseball caps, and it should never be used to clean them. However, you can use oxygen bleach to brighten a white hat safely or opt for natural cleaners like baking soda and vinegar.