How to Wash a Flag the Right Way with FlagOh

Washing a flag sounds simple, but one wrong hot cycle can melt fibers and strip the color from your favorite team banner or porch flag. Outdoor flags live in sun, rain, mud, and bird droppings, so they need more care than a load of towels. At FlagOh, after years of working with polyester, nylon, and POD inks, we know what keeps flags flying longer. This guide shows you how to wash a flag safely without ruining it.

Know Your Flag’s Fabric Before You Wash It

Before you even fill the sink, take a moment to check the tag—especially if you’re figuring out how to wash a flag at home for the first time. Not all flags are created equal, and treating a delicate burlap garden flag the same way you treat a heavy-duty polyester sports flag is a recipe for disaster.

Most of the flags we sell at FlagOh, and indeed most outdoor flags on the market today, are made of polyester (100D to 600D). This material is synthetic, durable, and designed to hold dye-sublimated ink exceptionally well. In flag specs, 100D to 600D refers to the denier rating—the higher the number, the thicker and harder-wearing the fabric for outdoor use. These are the workhorses of the flag world and are generally machine-safe if you’re careful, especially when you combine a gentle cycle with cold water and mild detergent.

Nylon is another common material, especially for official U.S. flags with sewn stripes and embroidered stars. It’s tough but can be sensitive to surface abrasion.

On the other hand, if you have a decorative burlap or linen garden flag, keep it away from the washing machine. These natural or porous fabrics hold too much water; a machine cycle will leave them misshapen, frayed, or prone to mold. Similarly, vintage cotton flags are incredibly delicate—they shrink easily, and their red dyes love to bleed into the white stripes. For these, gentle hand care is the only way to go.

The “Cheat Sheet” for Flag Materials

Material Type	Recommended Method	Water Temp	Bleach?	Drying
Polyester	Machine (Delicate)	Cold	NO	Air Dry
Nylon	Hand Wash	Cold	NO	Air Dry
Burlap	Hand Soak	Cool	NO	Lay Flat
Cotton	Hand Soak	Cool	NO	Lay Flat

How to Wash a Flag in a Washing Machine

Always start by checking the care label on your flag. If it says “hand wash only” or “do not wash, treat those instructions as your primary rule.

If you have a standard outdoor polyester flag (100D–600D) or a sports team banner, the washing machine is efficient—as long as you treat it like technical gear, not a bath towel. Most of the damage we see comes from hot water and high-speed cycles, not from the detergent itself. Follow these 4 steps to ensure a safe wash:

Step 1: Protect the Grommets (Crucial) 

The metal grommets on your flag are heavy and can bang against the washing machine drum during the spin cycle. This risks chipping your machine’s enamel or tearing the flag fabric.

• Action: Always place your flag inside a mesh laundry bag before loading. If you don’t have one, tie it securely inside a plain white pillowcase. This creates a safety barrier.

Step 2: Select the Safe Settings 

Standard cycles are too rough for flag headers and stitching.

• Cycle: Choose Delicate or Hand Wash to minimize agitation.
• Temperature: Set to Cold Water Only (<80°F / 27°C). Hot water is the enemy—it breaks down UV-resistant coatings and warps synthetic fibers.

Step 3: Add the Right Detergent 

Chemicals can do more damage than dirt.

• Do: Use a small amount of mild liquid detergent.
• Don’t: Never use fabric softener (it leaves a waxy residue that attracts dust) and never use chlorine bleach. Bleach will dissolve sublimation ink and turn your white stripes yellow.

Step 4: Remove Immediately 

Don’t let the flag sit in a wet heap once the cycle ends, as this sets deep, hard-to-remove wrinkles.

• Action: Remove the flag as soon as the washer stops. Support the weight of the wet fabric with your hands as you lift it out to prevent the heavy grommets from stretching the fabric, then go straight to air-drying.

How to Clean Delicate Flags Without Damage

For U.S. flags with embroidered stars, delicate burlap garden flags, or vintage pieces you’re afraid to risk, the “Bathtub Method” is the platinum standard. It gives you total control over the water temperature and handling.

Step 1: Prepare the Bath 

Start with a clean slate. Fill a bathtub or large laundry sink with cool water. Add a small capful of mild liquid detergent and mix it in with your hands until it’s evenly dispersed.

Step 2: The Soak (Crucial) 

Submerge the flag completely, ensuring no part is floating dry above the surface. Let it sit for 20–30 minutes.

• Why? This static soak allows the water and detergent to lift embedded dust and pollen out of the fibers naturally, so you don’t have to scrub hard later.

Step 3: Gentle Agitation 

After soaking, gently swish the flag through the water with your hands to simulate a slow wash cycle. If there are visible dirty spots, lightly rub the fabric against itself using your thumbs. Avoid aggressive scrubbing on embroidered stars or printed logos.

Step 4: Rinse Thoroughly 

Drain the dirty, soapy water and refill the tub with fresh, cool water. Swish the flag again to remove the detergent. Repeat this until no suds remain.

• Tip: Be thorough—leftover soap residue can bake into the fabric and turn brown when exposed to the sun.

Step 5: Extract Water (Do Not Wring) 

Carefully lift the flag and press it against the side of the tub to push the water out. Alternatively, sandwich the flag between two dry towels and press down.

• Warning: Never wring, twist, or “rope” the flag. This breaks the internal coating of the fibers and creates permanent creases that are nearly impossible to remove.

Step 6: Air Dry 

Move the flag to a drying area with good air circulation. Either hang it on a line (distributing the weight evenly) or lay it flat on dry towels. Keep it away from heaters or direct scorching sunlight while wet to prevent shrinking.

Deep Cleaning Tips for Heavily Soiled Flags

Sometimes, a standard wash just won’t cut it. Because outdoor flags are constantly exposed to sun, rain, and dirt, the best way to clean a flag is often to spot-treat the specific problem.

Mold and Mildew

If your flag has been hanging in a shady, damp spot, you might see black or green spots. Don’t reach for the bleach. Instead, mix a solution of white vinegar and water (1:1 ratio). Soak the moldy area for about 15 minutes, then gently scrub it with a soft-bristle brush (an old toothbrush is perfect). The acidity of the vinegar kills the mold without bleaching the color.

Tree Sap

This is a nightmare for flags parked under pine trees. Since sap is oil-based, water won’t touch it. The hack here is rubbing alcohol (or hand sanitizer). Dab it onto the sap to break down the resin, then rinse it off immediately.

Grease and Oil

Tailgating is fun, but BBQ grease is not. If your team flag gets splattered, apply a drop of dish soap directly to the dry stain before you wash it. Dish soap is designed to cut grease on pans, and it works just as well on polyester. Massage it in, let it sit for 10 minutes, and then wash as usual.

Bird Droppings

It happens. The trick here is patience. Let it dry completely so you can scrape off the solids first. Then, pre-soak the area in warm water with an enzyme-based detergent to break down the rest before washing.

How to Dry Your Flag Safely

If there is one thing you take away from this guide, let it be this: Never put a flag in a tumble dryer.

Synthetic fibers are essentially plastic. Even on a “low heat” setting, a dryer can get hot enough to warp the fabric, shrink the headers, or melt the specialized coatings.

Instead, hang the flag on a clothesline or lay it flat on a clean towel. It will dry quickly; just keep it out of direct, scorching sunlight while it’s very wet, as water droplets can act like magnifying glasses and cause spot-fading.

What about wrinkles? If your flag dries with creases, don’t panic. The safest way to smooth them out is with a garment steamer. It relaxes the fibers without touching them. If you must use an iron, use the “Synthetic” setting and always place a thick cotton towel between the iron and the flag. Never iron directly on the print—heat can reactivate the ink and cause it to smear or “ghost.”

Flag Etiquette and Maintenance

We often get asked, “Is it illegal to wash the American flag?” and see people searching “how do you wash an American flag” because they’re worried about doing something disrespectful. The answer is no. According to the U.S. Flag Code (4 U.S. Code § 8), the focus is on treating the flag with respect, not on banning normal cleaning. A dirty, soiled flag does not represent the country well, so washing a flag to restore it to a “fitting condition for display” is considered a respectful act.

However, cleaning has its limits. If your flag is badly tattered, the fly end is frayed beyond repair, or the red has faded to a pale pink, washing won’t bring it back. At that point, the right thing to do is retire the flag and dispose of it in a dignified way, often through a local American Legion, VFW post, or scout troop. Many of these organizations hold regular flag retirement ceremonies and can guide you on the most respectful way to hand your flag over.

To keep a new flag looking good for as long as possible, take it down when winds exceed about 40 mph, avoid flying it in severe storms, and consider using a UV fabric protector spray if it lives in direct sunlight.

In practice, inspect your flag at least once a month and wash it when it looks visibly dirty or after a heavy storm, instead of on every minor mark. This balance helps you keep it presentable without wearing the fibers out too quickly.

Learning how to wash a flag safely really comes down to a few basics. Match the method to the fabric, use cold water with a mild detergent, treat stains gently, and always air-dry instead of tumble drying so each wash extends its life. In our experience, flags cared for this way last noticeably longer and keep their colors stronger than those washed hot or run through the dryer. When a flag is too torn or faded to look dignified, retire it respectfully—and when you’re ready for a new one, choosing a durable outdoor or sports flag from FlagOh and caring for it with this routine will keep your colors flying bright.