How to wash microfiber towels (and why it matters)

Nothing touches your paint more often than your microfiber towels. A clean towel lifts dirt off. A dirty one drags it across the clear coat.

Here's the short version: sort towels by job, wash them in cold or warm water with a microfiber or free-and-clear liquid detergent, skip fabric softener, bleach and dryer sheets, and dry on low or no heat. Do that and your towels stay soft, absorbent and safe on paint.

The problem: a dirty towel scratches like sandpaper

A clean microfiber towel works because of how it's built. The International Detailing Association (IDA) explains that each strand "is split into numerous microscopic fibers, creating a network of tiny hooks and loops that trap dirt and absorb liquids." (IDA: The Art of Washing Microfiber Towels)

That same grip is the problem when a towel isn't clean. Grit, brake dust and dried polish stay trapped in the fibers. The next time you wipe the hood, the towel drags that debris across the clear coat. One wipe won't show. Wash after wash, the fine scratches add up until you see them in direct sun as the circular scratches and haze we call swirl marks.

Here's what's at stake for you as the owner:

Swirls and scratches. They're cut into the clear coat, so no soap or wax washes them out. Once they're there, the fix is machine polishing (paint correction), which removes a thin layer of clear coat to level them. Clear coat is thin, and it doesn't grow back.
Streaks and smears. Softener and fragrance residue left in a towel gets wiped right back onto your glass and paint.
Towels that stop working. Clogged or heat-damaged fibers stop absorbing and stop grabbing dirt, so you rub harder to get the same result. More pressure means more risk.
A whole load ruined at once. One wash with the wrong detergent or high heat can leave every towel in the machine stiff, streaky and unsafe on paint.

The certified detailer who wrote the IDA's guide puts the powdered-detergent mistake bluntly: towels trap the powder, "ruining an entire load of towels. Would you use them on soft black paint after that? I wouldn't." If you own a dark car, our black car care guide shows how fast those marks show up.

We broke down the other big wash-day culprits in 5 washing mistakes that cause swirl marks. Dirty towels sit right alongside them.

Step 1: Sort your towels by job

Before anything goes in the washer, sort it. The IDA's first rule: "Microfiber towels used for different purposes should be washed separately. For instance, towels used for cleaning glass should be washed separately from those used for automotive detailing." That keeps wax, dressing and grime from one job out of the towels for another.

At home, four piles cover almost everyone:

Paint: wash mitts, drying towels and the towels you use for quick detailer or rinseless washes.
Glass: your glass towels, kept apart so they don't pick up wax or dressing.
Interior: dash, door panels and screens.
Wheels, tires and door jambs: the dirtiest jobs.

A color system makes this easy. Pick one color per pile and stick with it. Wheel towels never go back on paint, even after a wash. When a paint towel gets old or stained, demote it to wheels and jambs instead of throwing it out.

Two more house rules: if you drop a towel, it's out until it's washed, and never wash microfiber with cotton. Cotton sheds lint that clings to microfiber and then ends up on your paint.

Step 2: Shake out and rinse heavy grime

Shake each towel out before it goes in, outside and away from your clean towels. Loose grit, sand and dried product come off easier dry.

Towels caked with polish, wax, dressing or brake dust benefit from a soak or rinse in a bucket of warm water with a little microfiber detergent first. Then wash them in their own load, separate from your paint and glass towels.

Step 3: Use the right detergent

This is where most home washes go wrong. The IDA notes that everyday laundry detergent is "normally designed to remove food and sweat stains out of clothing and loaded with fabric softeners and fragrances. These are left behind in the towels, making them streaky when they encounter water or become less absorbent!"

Powder is worse. Per the IDA, "these powders do not break down!"

What to use instead:

A microfiber-specific liquid detergent. The IDA says, "We recommend, as other microfiber manufacturers do, using a microfiber specific liquid detergent."
Or a free-and-clear liquid detergent. The IDA lists "either a Free & Clear detergent or a microfiber specific detergent" as the right choices.

Use the amount on the detergent label. More soap isn't cleaner. It's just more to rinse out.

Step 4: Wash cold or warm on a gentle cycle

Set the machine up this way:

Water temperature: the IDA says microfiber "can be safely washed in cold or warm water, but NEVER hot water, as it can damage the fibers."
Cycle: "Use a Gentle or Delicate Cycle," the IDA says, and "Choose a wash cycle with a low spin speed" to go easy on the fabric.
Load size: "Do not overload the washing machine." Towels need room to move to get clean.
No fabric softener and no bleach. The IDA warns they "can damage the microfiber structure and reduce its cleaning efficiency."

An extra rinse cycle is a cheap way to make sure no detergent stays in the fibers.

Step 5: Dry low, or hang dry

Heat is the other towel killer. The IDA's rule is "LOW or NO Heat Drying," because "Using high heat causes the fibers to dry out and become arthritic, making them less dexterous in cleaning and unable to dry as effectively."

Tumble dry on low or no heat, or hang them to air dry out of direct sun and dust.
No dryer sheets. The IDA says they "can leave residues on microfiber towels, diminishing their cleaning abilities."
Clean the lint trap first and dry microfiber by itself, so it doesn't pick up lint from your laundry.

Step 6: Store them like they touch your paint

Because they do. Once they're dry, fold the towels and store them in a closed bin or zip bag, sorted by color. An open garage shelf collects dust, and dust is exactly what you're trying to keep off your car.

Before a towel touches paint, give it a quick look and feel. If it feels stiff, crunchy or gritty, it goes back in the wash or down to wheel duty.

Step 7: Keep your washer clean

Residue in the machine ends up back in your towels. The IDA's advice is to "Clean your washing machine regularly," since "detergent and lint buildup" can affect how clean your towels come out.

Towels used with ceramic sprays and coatings

Ceramic sprays and coatings are built to bond to paint and harden. That's how they help protect your paint, and it's also why they're hard on the towels that wipe them off. A lot of the leftover product ends up in the fibers, where it keeps curing after the job. Hardened fibers aren't safe on paint again.

A regular wash and dry may not get it out. The towel can come out of the dryer looking clean with stiff, residue-loaded fibers still inside. Put it back on your paint and it can drag and mar the clear coat, or smear old product into streaks and high spots. On a coated car, that's damage to the finish you paid to protect, and fixing marring or a cured high spot usually means polishing.

Towels used with spray-on ceramic sealants and toppers: keep them out of your regular load. Soak them for a few hours in a bucket of water with a microfiber detergent like Micro-Restore, then wash them on their own. Micro-Restore is a strong alkaline cleaner, so wear gloves. After that, we only use those towels on interiors. They don't go back on paint, and yours shouldn't either.

Towels used to level and buff a ceramic coating: we throw them away. Some people soak and wash these too, and some towel makers say they can be reused after a proper wash. In our experience, the soak doesn't bring them back, and one towel isn't worth the risk to a fresh coating.

When to retire a towel

The IDA says to "regularly inspect your microfiber towels for damage. If you notice fraying, snags, or excessive wear, it might be time to replace them."

A towel is ready for retirement (or wheel duty) when:

It feels stiff or flat, even after a proper wash.
It smears water around instead of soaking it up.
The edges are fraying, or the stitching is pulling loose.
It has stains from polish, sealant or grease that won't wash out.

Does GSM matter when you buy towels?

GSM (grams per square meter) is the weight printed on most towel labels. A bigger number isn't automatically a better towel. The IDA notes, "The raw materials, like the yarn, and the overall construction are more important to the quality of the towel than the weight or GSM." (IDA: Microfiber Towels: What is GSM?)

Buy fewer, better towels, and take care of them. If you're building a kit on a budget, start with our budget car care routine.

Clean towels make every wash safer

Clean towels matter for every way you wash at home. If you wash without a hose, our rinseless car wash guide goes through a stack of clean towels per car, and every one of them needs to be clean before it touches paint. The same goes for drying. San Diego's water is hard, so you want an absorbent towel that gets the car dry fast, before minerals dry on the paint. Our hard water spots post explains why.

Clean towels also matter for quick cleanups, like lifting off fresh bird droppings before they etch.

If your towels have already left swirls

Washing your towels right helps you avoid adding new swirls. It won't remove the ones already cut into the clear coat. If you see fine circles or haze when the sun hits your paint, paint correction machine-polishes them out and brings back clean, sharp reflections.

Once the paint is corrected, a ceramic coating helps protect that finish. It adds deep gloss and a slick, strongly hydrophobic layer between the clear coat and UV, bird droppings and road fallout. Grime doesn't bond as hard to a coated surface either, so washing takes less rubbing and your clean towels glide instead of drag. See what a ceramic coating does, then compare P&S Inspiration STOUT and SystemX Phantom in choose your coating.

FAQ

How often should I wash my microfiber towels?

After every use on your car. A towel that has wiped dirt, polish or dressing should be washed before it touches paint again.

Why do my microfiber towels leave streaks?

Usually it's leftover residue: fabric softener, fragrance, detergent, or wax from a mixed load. Rewash them by themselves with a microfiber or free-and-clear detergent and an extra rinse. If they still streak, retire them to wheel or jamb duty.

Can a dirty microfiber towel scratch my paint?

Yes. Microfiber is built to trap particles, so grit left in the fibers gets dragged across the clear coat on the next wipe. That's how swirl marks go on.

Book your free consult

Seeing swirls in the sun? Tell us what your paint looks like, and we'll talk through whether correction, a coating or both makes sense. Book your free consult.

Sources

International Detailing Association, The Art of Washing Microfiber Towels: IDA microfiber washing guide
Detailing Nearby by IDA, Microfiber Towels: What is GSM?: IDA microfiber GSM guide