How to Clean a Baseball Cap with Cardboard Bills
Photo by Keith

How to Clean a Baseball Cap with Cardboard Bills

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Baseball caps can get mighty dirty, which poses a challenge with that pesky thing sticking out the frontside. Will the bill, or as some call it brim, do well in washes? If the bill shrinks or breaks form, does it wreck the rest of the hat? How do you clean a baseball cap with cardboard sewed inside the brim?

Cleaning baseball caps with cardboard bills is doable, with very great care. Despite commonly held misconceptions about using dishwashers or regular clothes washing machines, the best way to clean baseball caps is to hand-wash (carefully), and let them air-dry. Before leaving out to air dry, set the moist cap around and on top of something to keep its form.

While it’s true that dishwashers or washing machines could be used to clean baseball hats, it’s not recommended. Maybe for caps you don’t mind looking worn, or without original shaping ~ or maybe if they’re what are known as “beaters” or “toss-aways” ~ washing by electric gadgets may be okay.

But for any baseball cap of value, whether monetarily or sentimentally, wash them tenderly by hand, dab (not wipe) them as dry as possible, set them on something to hold the round crown shaped like you want it, and let air do the drying.

The Right Way to Hand Wash Baseball Caps

Cleaning baseball caps is easy, actually. Just prepare by having one large towel and probably 2 or 3 clean dry towels for dabbing and drying, and a small bucket ready to fill halfway with lukewarm water. Let’s start with cardboard-brimmed baseball caps, because they can only be spot-cleaned (getting them entirely wet, especially the bill, can deform bill and possibly shrink the headband):

  1. Fill a gallon water bucket (or suitable small bucket) halfway, and drop in a few drops of dishwater detergent, or a liquid or pod clothing detergent. You don’t need to use too much detergent; water alone can do a lot of hat cleaning, aided by damping.
  2. Once detergent is dissolved, take a clean small towel and drench it in the water. Take it out, squeeze excess water out.
  3. Lightly press onto stains, spots, salt lines, and inside the headband, to make them moist. Dab and solidly press the clean wet towel onto especially dirty areas, over and over. Don’t be afraid to get much of the hat fairly wet ~ except the bill which needs to be carefully dabbed, and maybe softly wiped off.
  4. Be careful not to roughly wipe fabrics (except the headband). Dabbing is better, with plenty of water.
  5. Pay attention to the inner headband, often soaked with sweat, salt, and dirt. Buff it well ~ the inside of the cap is okay for hard wiping ~ and again don’t be afraid to get it quite wet. This area of the hat is designed to absorb sweat and dirt.
  6. Repeat wet-and-dab, and buff in places, until satisfied that the most-troubled stains and dirt are gone. At the end, really soak one dry clean towel and use it to softly wipe over the entire cap, grabbing any loose dust or light dirt.
  7. Leave the cap out to air dry; put something under the crown to hold its shape while the hat dries, like a large ball of crumpled newspapers, or a large coffee can.

The same instructions can be applied to more modern baseball caps with plastic-supported bills, only you don’t have to be ultra-careful with wetting the bill.

Washing Baseball Caps in a Dishwasher

This method has been used by many ball cap wearers, and some swear by it. It’s as easy as setting it atop the upper rack of the dishwasher, where they usually place cups and glasses, and turning it on to wash.

There are tips, too, like using something to place inside the crown to help retain its shape through the wash cycle; or, washing it alone and not with dishes inside.

Often, caps come out squeaky clean, albeit drenched. They can be air dried from there.

However, it poses several problems:

  1. Even if no detergent is used during a cycle, remnants from cleaning chemicals from past cycles remain inside the washer, and could damage the color or material of a baseball cap.
  2. Heat: be certain the heat-drying option is off; heat is a known enemy of baseball caps.
  3. Too many cycles; jostling caps around in water is not always a great idea.


No matter which cleaning tactic you use, once a cap is done through a wash cycle, and quite wet, use something to set inside the crown to let it dry into the right shape. Whatever it is, it should prevent the crown from sinking or leaning one way during the drying process.

Why Cleaning Baseball Caps in Washing Machines is Bad

For washing machines, it can be tempting to just toss the cap into the machine along with your baseball wear. And some people do this ~ if the cap doesn’t need to look great, as in a practice cap, or “toss-away” cheapie.

Washing machines can be even worse than dishwashers, because the caps get squished around other garments during cycles, and then, probably worse, get spun hard to squeeze out excess water. This spin-dry process is not good for baseball hats. Especially if you fail to take them out immediately and do something to return the shape.

On top of that, there’s the same problems as the dishwasher: hot water, and remnants of previously used cleaning chemicals.

Cardboard Bills on Baseball Caps

Up until about 1983, the bills on baseball caps were made of cardboard, carefully sewn under thin layers of cotton or vinyl on top and bottom. Those hats should never be tossed into an electronic cleaning contraption, nor even dipped entirely in water.

The cardboard will misshape badly, to shrink or even eventually disintegrate. If you clean a baseball cap with a cardboard bill or brim in any type of electric washing machine, it might be the only time you do so. Certainly, washing them that way more than once will eventually mean the total demise of the cap.

Even baseball caps manufactured after 1983, with a light type of plastic inside the bills, don’t fare well with being totally drenched in water, which sometimes still contains cleaning chemicals from previous wash cycles. Not to mention the jostling around other garments, or heated water.

Baseball caps are garments with sensitive headbands, usually fitted for comfort. Too much water, or heat, or both, can disfigure or shrink the headband, making the cap unwearable. Even snap-back adjustable caps are prone to damage by cleaning chemicals inside machines.

How Often Do Baseball Caps Need Cleaning?

How much to wash baseball caps totally depends on their use, and desired purpose by the owner. For example, following are types of uses for ball caps, and typical desires for those who own them:

Baseball Cap Uses

  • To play baseball
  • To play other sports, like tennis or golf
  • To protect eyes from the sun or sweat (e.g. while hiking, exercise, outdoorsy stuff)
  • Show support for a sports team, cause, product, or brand
  • As a fashion accessory
  • Hide bald spots
  • Keep long hair out of eyes
  • To make a statement (at locations that forbid hats, for instance; or caps with controversial messages on them)

The key here is intensity of usage. Anything that makes a person sweat a lot, especially if that activity is on dirt or grass, will stain or dirty baseball caps faster than just wearing them for how they look.

Baseball Hat Purposes

After considering usage of baseball hats, then think about what you want from it:

  • To last as long as possible
  • To last long and look perfect as long as possible
  • Just to have something around to thrown on a head to protect from sunlight, rain, or bad hair days
  • To show off (but not very often, e.g. collector’s caps, very unusual baseball hats)
  • Just one in a great collection of caps (usually this is for people who wear baseball hats a lot)

Final Words on Cleaning Baseball Caps with Cardboard Brims

The best way to clean a baseball cap is to hand-wash it carefully, dab at trouble spots with wet clean towels, and air dry hopefully with something the crown to keep its shape. Types of cleaning that use chemicals, heat, or powerful spin-drying can be harmful to baseball caps, both for their color, seams, and stitching, and of course the sensitive bill.

Related Questions

Question: How can you tell if my cap has a cardboard bill?

Answer: Grip one side tightly with your fingers, and on the other side tap on it a few times (or flick the edges). If it sounds hollow, it’s probably cardboard. Newfangled bills sound like, well, tapping on light plastic.

Q.: Can you dry clean a baseball cap with cardboard bills?

A.: Yes. In fact, this may be preferable even to hand-washing ~ just try not to over-do it. Especially for collector’s or old caps, dry cleaning uses chemicals, too, which might not be appropriate for the makeup of all caps. And too much dry cleaning over time is not good for any garment.

See Also:
New Era vs. Flexfit Hats: The Titans of Baseball Caps
7 Best Sunglasses to Wear with a Baseball Cap
Why Do People Wear Baseball Cap Backwards?
Why is Shortstop the Hardest Position in Baseball?