How Dry Cleaning Works

We are going to tackle one of life’s biggest mysteries – how does dry cleaning work?

All most people know is that they drop off their delicates, their suits, their fancy dress shirts, etc. at the dry cleaners, and the next day they come back pressed, stain-free, and beautiful!

It is truly a modern wonder. How does a cleaning process that uses no liquid clean your clothes and remove stains?

Well, the answer is, it doesn’t.

Here’s a shocking fact: dry cleaning is not actually dry.


That’s right! You’ve been lied to all these years.

While the dry cleaning process does not use any water, it is not a dry process. It uses other liquid chemicals to get rid of your stains and clean your clothes.

“Well, I’ll be darned!”, you’re probably thinking.

Eager to find out how it works?

By the end of this article, you’ll be an expert on dry cleaning. The next time your colleague says she has to go to the dry cleaners, you’ll be able to drop this newfound knowledge on them.

A Little Bit of History

Fun fact: gasoline/kerosene is actually a phenomenal stain remover!

We won’t bore you with the details, but the story goes that some guy in the 1800s spilled gasoline on a tablecloth and noticed some of the stains started to disappear.


Could he have discovered something better than just plain old soap and water?

Answer: yes!

Gasoline/kerosene was among the first liquids to be used to get rid of stains.

However, due to the flammability of these (duh), other chemicals started to be explored.

The new industry standard is a chemical solvent called tetrachloroethylene., or as the industry experts call it: ‘perc’.

Much easier to pronounce than tetrachloroethylene. Unless you’re a chemist.

Anyway, we’re just happy that cleaners don’t use gasoline to use our clothes anymore.

So, How Does the Process Work?

Ugh, we are so glad you asked!

Well, this is the whole point of the article. There are five different stages of the process and we’ll walk you through.

Of course, this is only the general process, and it might vary slightly from dry cleaner to dry cleaner. But this is basically what happens in the 24 hours between when you drop off your clothes and when you pick them up.

One small thing to note is that a lot of modern-day dry cleaners actually don’t have the equipment on-site to wash your clothes.

In almost every scenario they send them away to a larger facility to washes everyone’s clothes, then sends them back out accordingly.

They will, however, oftentimes put the finishing touches on in the store (more on that later).

The ProcessTagging

1. Tagging

Perfect, so you finally got enough energy to gather up all of your most expensive clothes and lug them to the dry cleaners.

When you first get there, they have to tag each and every single one of your garments.

Usually, they’ll staple a tag to it or if you’re a regular customer, they may put a permanent barcode on a nondescript part of the garment.

Like we mentioned before, they are going to be sending your clothes away so it’s 100% necessary that they get tagged.

During this stage, they will also inspect for any damages (rips, missing buttons) and also any stains that may require more work.

If it requires any extra special stain treatment, they will mark it accordingly, so they can keep track of what needs to be done.

They will take all of this information and enter it into a computer to help keep track of everything.

Most people leave some of their most expensive clothes with a dry cleaner so it’s essential that they don’t lose anything!

2. Pre-Treating Stains

This is an essential part of the dry cleaning process.

They’re going to pre-treat any heavily soiled stains that they might find.

They will use water for wet stains and a solvent for dry stains (any stain that has grease or oil in it). We did say water but don’t worry, they won’t completely soak your shirt.

This is simply a spot treatment where they’re going to blot the stains and make it just a little bit easier for the chemicals to break down the stains later.

If you notice a fresh stain or want to help the process along, you can actually also pre-treat the stains at home.

The more attention that a stain gets, the better.

By doing this, you give your stain a lot better of a chance of being removed.

3. The Actual Dry Cleaning

Alright! Now for the actual dry cleaning process. So, what happens?

After pre-treatment, all your clothes are put into (essentially) a giant front-loading washing machine.

They look very similar to yours except much much larger. It has a perforated stainless-steel basket that allows for liquid to enter and exit.

In just about all modern equipment, the washing machine also doubles as the dryer!

How convenient.

The machine then fills up with the perc (and a couple of other water-free solvents). The machine then gently swishes the clothes around in the liquid to help break up the stain and lift it from the clothes.

The solvent, combined with the pounding of the clothes against the drum really helps to get the stains out.

This process is most effective on oil-based stains and isn’t necessarily perfect for water-based stains.

Hence why there is a pre-treatment (and also a post-treatment) process.

Unlike regular at-home washing, there is new perc being filtered through the entire time.

The dirty solvent comes out, is completely filtered through a distilling process, and then new solvent pumped through.

This helps to get rid of the stain as there is constantly fresh perc coming through attacking the stains.

On stains that are particularly troublesome, sometimes petroleum solvents will be used.

These solvents are insanely flammable, so many fire prevention steps must be put in place.

The cleaner must also be attentive with cleaning the filter as this whole process is happening.

Why is it so important?

They need to make sure there is no moisture build-up. If too much moisture builds up, it can defeat the whole purpose of dry-cleaning!

4. Post-Treatment

Voila! All done.

Not quite, actually.

Post-treatment is a very important part of the quality control process. The cleaner will now double-check that all of the stains are out and also give any extra attention to stubborn stains.

This is essentially the same as the pre-treatment stage.

They will use wet treatment techniques or more solvent (depending on the stain) to remove any last remnants.

In regular washing at home, wet stains generally come out and dry stains do not.

At the dry cleaners, the opposite is generally true. Now, most wet stains will be spot treated.

5. Getting Ready for Collection

Once all the stains are out, it’s time to get your clothes pretty and ready for collection!

Now they will gently steam the garments, press your clothes, attach any missing buttons, re-shape the garment, etc.

This is the part of the process that a lot of dry-cleaners will do on-site

Environmentally Safe Dry Cleaning

Sounds like a lot of chemicals are involved, doesn’t it?

You’re not wrong.

That’s why there’s a new trend emerging right now: environmentally safe dry cleaning. There have been a few new regulations emerging that are forcing a lot of dry cleaners to do this.

So, a new method of carbon-dioxide-based cleaning is now being used as an alternative to traditional methods.

However, this is a whole different process that we won’t get into right now.

Dry Cleaning Symbols

Don’t worry. Dry cleaners don’t just guess what to do. They follow a specific code to make sure your clothes won’t get ruined.

There are international GINETEX laundry symbols that say exactly what to do.

Take a look.

The P indicates that you should use the tetrachloroethylene solvent.

The F indicates to use a flammable solvent.

  • Professional Cleaning Symbol

  • Dry clean, hydrocarbon solvent only (HCS)

  • Gentle cleaning with hydrocarbon solvents

  • Very gentle cleaning with hydrocarbon solvents

  • Dryclean, tetrachloroethylene (PCE) only

  • Gentle cleaning with PCE

  • Very gentle cleaning with PCE

  • Do not dry clean!


Once you know how dry cleaning works, it’s really not that crazy of a process.

We still aren’t sure why they call it dry-cleaning in the first place, but hey. Technically it doesn’t use any water.

Hopefully, this helped clear things up and as always, thanks for reading!

Until next time, friends.

Justin Howe

Electrician and DIY specialist Justin deleted his own successful tech blog to write expert product reviews and buying guides together with his friend Robert.

Justin Howe

Electrician and DIY specialist Justin deleted his own successful tech blog to write expert product reviews and buying guides together with his friend Robert.