How To Descale Keurig K-Slim (Step By Step!)

Like with every other coffee maker, you have to descale your Keurig K-Slim every now and then.

With other coffee makers, you might just throw some vinegar in, rinse it a couple of times and call it a day. But with the Keurig K-Slim, you have to follow a whole descaling procedure before the descaling light will come off.

In this article, I will tell you exactly how to descale a Keurig K-slim coffee maker.

How To Descale a Keurig K-Slim Coffee Maker?

To descale your Keurig K-Slim, you first want to add a bottle of Keurig descale solution and add the same amount of water to the tank. Hold the 8 and 12oz buttons until the descale light comes on solid and the “K” button starts blinking. Press the K button two or three times until the add water light comes on after that clean the water tank and fill it with fresh water. Press the K button 4 to 5 times until the K-Slim turns off and you’re done.

Scroll down to get some more detail on this process!

how to Descale Keurig   

Table of Contents

Things To Know Before Descaling Your Keurig K-Slim

When your Keurig coffee maker starts making some more noise or the coffee starts tasting different, you know it’s time to descale it. You really want to descale it at least every three months, especially when you’re using unfiltered water.

Your coffee maker has a descale light, that indicates it needs descaling after 250 brews. You don’t necessarily have to wait for the light to come on before you can descale your coffee maker.

With older Keurig models you could just put some vinegar or descale solution in the coffee maker and run some brews and rinses and the descale light would come off.

With the Keurig K-Slim and some other newer models like the K-Express and K-Supremeyou need to put it in “descale mode” and go through the whole process before the light goes out and you can make a cup of coffee again.

The descaling procedure to follow did come with the original manual when you first bought your Keurig machine.

Put Descaling Solution In The Water Tank

The first thing you want to do is take out the water reservoir and pour out the remaining water. If you got a water filter in there, you need to remove that as well. Then pour the descaling solution into the water tank.

If you’re using the Keurig descaling solutionpour the entire contents of the bottle into the water tank. Top up the rest with water until you have about a 1/1 ratio of water to the descaling solution.

An easy way to get the exact one-to-one ratio is to fill the descale solution bottle you just used with water and pour that into the tank.

Once you’ve done that you notice that the tank is not filled to the max. That doesn’t matter because you want to keep that one-to-one ratio of water to descale solution.

Put Your K-Slim In Descale Mode

Now that you got the water tank filled up with the descaling solution and water, you want to put the water reservoir back in the coffee maker. Make sure that there is no K-cup in your Keurig Slim. The K-cup holder can stay in there. Now let’s put it in descaling mode.

To put your Keurig K-Slim into descaling mode. First, turn off your coffee maker but keep it plugged in. Next, press the 8 and 12 oz buttons simultaneously for three seconds until the “K” button starts blinking and the descale light comes on solid.

Now you’ve put your coffee maker in descaling mode. The K button should be blinking and the descale light should be on solid.

Start The Descaling Process

Once your Keurig K-Slim is in descaling mode, do not lift the lid or unplug it.

All you need to do now is place a container under the coffee maker and press the “K” button until the “add water” light begins to flash. This will probably happen after you press the K button twice, but in some cases, you may need to press it a third time.

It will run the descaling solution through to clean the heating element and tubes.

Contrary to brewing a normal coffee. When descaling your coffee maker, it might splatter a bit because the water is pouring out so slowly. Putting a towel around your coffee maker could be a good idea.

It is important that you do not press the K button again if the “add water” light begins to flash. Even if there is still some descaling solution in the tank.

Doing this can mess up the descaling mode resulting in the descale light staying on even when you just descaled it.

Now you want to take out the water reservoir and clean it out with some soap and water. Then fill it up to the max with fresh water without descaling the solution in it.

Put the water reservoir back in the coffee maker, the “add water” light should go off, the descale light should be on solid again and the K light should still be blinking.

Then you want to push the K button again until the K-Slim turns itself off. Now your Keurig is out of descaling mode. When you turn it on again you can brew a cup of coffee like you normally would!

This descaling process also cleans the needles very well. So, when you open the lid you might want to dry the inside with a towel because it can get a lot of steam and water on it.

keurig coffee

What To Do When The Descaling Light Stays On?

In some cases, the descale light still stays on after this whole procedure. This can happen if you made one little mistake in the process.

When your coffee maker doesn’t go out of descaling mode. The first thing you could try is unplugging it and waiting about three to four minutes before plugging it back in again.

If that didn’t work the easiest way to fix this is to do the whole descale procedure again. But this time you can just use water for all the steps since you’ve already descaled your coffee maker with the Keurig solution.

Check out this article for more detail on why the light on your Keurig K-Slim might not turn off and what you can do about it.

Can I Use Vinegar For Descaling My Keurig K-Slim?

Using white vinegar for descaling your Keurig K-Slim is fine. You’ll probably save some money compared to using the official Keurig descaling solution.

Make sure to use 14oz of vinegar and 14oz of water to clean and descale your Keurig coffee maker.

If you’re going to use vinegar also make sure to do some extra water rinses afterward, just to make sure that your coffee maker is clean and because vinegar has more smell than the normal Keurig solution.


Unlike with other Keurig models, descaling your Keurig K-Slim can be a little confusing. To recap here are all the steps to take:

  1. Add a bottle of Keurig descale solution and the same amount of water to the tank.
  2. Hold the 8 and 12oz buttons until the “K” button starts blinking and the descale light comes on solid.
  3. Press the K button two or three times until the add water light comes on.
  4. Clean the water tank and fill it with fresh water.
  5. Press the K button 4 to 5 times until the K-Slim turns off.

I hope that this article helped you with cleaning and descaling your Keurig K-Slim and that you can enjoy a good cup of coffee again!

Thanks for reading!