Descaling removes mineral buildup inside your Keurig so water flows properly and coffee tastes fresh

Descaling is running a cleaning solution through your Keurig to dissolve calcium and mineral deposits that accumulate from tap water. Over time, these deposits slow the water flow, make brewing take longer, and can affect the taste of your coffee. Most Keurig models need descaling every three to six months, depending on your water hardness—if your tap water is very hard, descale every three months.

The process takes about 30 minutes total and uses a descaling solution (citric acid or a commercial Keurig descaling kit) mixed with water. You run this solution through the machine without coffee grounds, then flush the system with fresh water. The good news: you do not need to take the machine apart, and the whole process is straightforward enough for a first-timer.

Key Takeaways

  • Descale your Keurig every three to six months by running a descaling solution through the brew cycle without coffee grounds.
  • You can use commercial Keurig descaling solution or make your own with citric acid and water in a 1:2 ratio.
  • The descaling cycle takes about 25 minutes, and you must flush the machine with fresh water afterward to remove all cleaning solution.
  • If your Keurig has a descale button, press it to enter descale mode; if not, straightforward run the solution through as you would brew coffee.
  • Never use vinegar in a Keurig—it can damage the internal seals and is not recommended by the manufacturer.

What you need before you start

Gather these items before you begin: a descaling solution (either a Keurig-brand descaling kit or citric acid), a large mug or container that holds at least 10 ounces, and fresh water. If you are using citric acid powder, mix one part citric acid with two parts water—for example, 1 tablespoon of citric acid mixed with 2 tablespoons of water. Keurig descaling kits come pre-mixed and ready to use; one bottle typically descales one machine.

Check your Keurig model to see if it has a dedicated descale button. Newer models (K-Supreme, K-Elite, K-Duo, and most models made after 2015) have a button labeled "Descale" on the control panel. Older models do not have this button and require you to manually run the solution through. Either way, the process is nearly identical—the button just automates the timing and alerts you when to refill the water reservoir.

Step 1: Empty the water reservoir and fill it with descaling solution

Turn off your Keurig and unplug it. Remove the water reservoir from the back or side of the machine (the exact location depends on your model). Empty any remaining water and rinse the reservoir with fresh water to remove any coffee residue or debris.

Fill the reservoir with your descaling solution—use the full bottle if you are using a Keurig kit, or pour your homemade citric acid mixture into the reservoir. Do not dilute it further; the solution needs to be at full strength to work. Reattach the reservoir to the machine and plug it back in.

Step 2: Run the descaling cycle

If your Keurig has a descale button, press it now. The machine will enter descale mode and display a message on the screen (usually "Descale" or a similar indicator). If your model does not have a descale button, straightforward proceed as if you were brewing a cup of coffee—place a large mug or container under the brew head to catch the solution.

Press the brew button (or the button for your preferred cup size if your model has multiple options). The machine will begin pumping the descaling solution through the internal lines. This first cycle takes about 4 to 5 minutes. Let it run completely—do not stop it halfway through. Empty the mug when it finishes and place it back under the brew head.

Repeat this process until the water reservoir is empty. Most Keurig machines require two to four brew cycles to empty the full reservoir, depending on the model and cup size selected. This entire descaling phase takes about 15 to 20 minutes.

Step 3: Let the machine sit and soak

Once the reservoir is empty, turn off the machine and let it sit for 15 to 30 minutes. This soaking time allows the descaling solution to break down stubborn mineral deposits inside the heating element and water lines. You do not need to do anything during this time—just leave the machine powered off.

This step is especially important if you have not descaled in a long time or if you have very hard tap water. The longer soak helps dissolve buildup that a single pass of solution might not reach.

Step 4: Flush the system with fresh water

After the soak, refill the water reservoir with fresh, clean water—do not add any more descaling solution. Plug the machine back in. If your model has a descale button, press it again; the machine will now run in flush mode. If your model does not have a descale button, straightforward brew as normal.

Run at least five full brew cycles using only fresh water. Place your mug under the brew head each time and let the water flow completely through. This flushes out all remaining descaling solution from the internal lines. The water should run clear by the third or fourth cycle, but continue until you have completed at least five cycles to may support no solution remains.

If your machine displays a "Descale Complete" or similar message after the flush cycles, that means the descaling process is finished. Some models automatically exit descale mode once the reservoir runs dry during the flush phase.

Step 5: Brew a test cup and clean the external parts

Fill the reservoir with fresh water one more time and brew a normal cup of coffee (or just hot water if you want to test without wasting coffee). This test cup ensures the machine is working properly and no descaling solution remains. The water should flow smoothly, and the brew should taste normal—not sour or chemical-tasting.

While the machine is running, wipe down the exterior with a damp cloth to remove any dust or spills. If your model has a removable drip tray, empty it and rinse it under running water. Check the K-Cup holder (the part where you insert the pod) for any mineral deposits; if you see white or gray buildup, use a damp cloth or an old toothbrush to gently scrub it away.

Common mistakes to avoid

Never use vinegar in a Keurig, even though vinegar is a common descaling agent for other coffee makers. Keurig's internal seals and components are not designed to handle vinegar's acidity, and using it can damage the machine and void the warranty. Stick to citric acid or a Keurig-brand descaling solution.

Do not skip the flush phase. Leftover descaling solution will make your next few cups of coffee taste bitter or sour. Run at least five full cycles of fresh water through the machine, even if the water looks clear after three cycles. Also, do not try to descale with a K-Cup still in the holder—remove it first so the solution flows through the entire system.

Avoid descaling too frequently. Once every three to six months is sufficient for most households. Descaling more often than that can wear out the internal pump and is unnecessary unless you have extremely hard water. If you notice your Keurig is brewing slowly again within a month of descaling, your tap water may be unusually hard, and you might benefit from using filtered water in the reservoir.

Frequently Asked Questions

How do I know when my Keurig needs descaling?

The most obvious sign is slower brewing—water takes longer to flow through the machine than it used to. Some Keurig models display a "Descale" light or message on the screen when minerals build up. If you have not descaled in more than six months, it is time to do it regardless of how the machine seems to be performing.

Can I use store-bought descaling solution from other brands?

Yes, as long as it is citric acid-based. Many universal descaling solutions work in Keurig machines. Avoid vinegar-based solutions and anything labeled for espresso machines or commercial equipment. When in doubt, check the product label to confirm it is safe for single-serve brewers.

What if water still drips slowly after descaling?

Run the descaling cycle one more time, paying special attention to the 15- to 30-minute soak phase. If the problem persists after a second descaling, the issue may be a clogged needle (the small tube that punctures K-Cups). Use a straightened paperclip to gently clear any debris from the needle, or contact Keurig support for further troubleshooting.

Is it safe to drink the water that comes out during descaling?

No. The water and descaling solution that flows out during the descaling and flush cycles should be discarded. Do not drink it or use it for cooking. The solution is designed to dissolve minerals, not for consumption.

Do I need to descale if I use filtered water?

Filtered water reduces mineral buildup, so you may be able to descale less frequently—perhaps every six to nine months instead of every three to six months. However, even filtered water contains some minerals, so descaling is still necessary. Check your machine periodically for signs of slow brewing, which indicates it is time to descale.