Replace the filter cartridge every two months, or when water flow slows

Your Keurig water filter sits inside the machine's water reservoir and catches sediment, chlorine, and minerals that affect taste and machine lifespan. When you replace it, you're swapping out a small cartridge that looks like a plastic tube with a mesh screen inside. Most Keurig models use the same replacement process: pull out the old cartridge, rinse the new one, soak it in water for 15 minutes, then slide it back in. The whole job takes about five minutes of hands-on time, plus the soaking period.

You'll know it's time to replace the filter when water flows more slowly through the machine, or when your coffee tastes off even though you're using fresh beans. Some Keurig models have a filter indicator light that turns on around the two-month mark. Even if the light doesn't come on, changing the filter every 60 days keeps your machine running smoothly and your coffee tasting clean.

Key Takeaways

  • The water filter cartridge sits inside your Keurig's reservoir and needs replacement every two months or when water flow slows noticeably.
  • You must soak a new filter cartridge in water for 15 minutes before installing it, or the machine will not dispense water properly.
  • The replacement cartridge is a small plastic tube that slides into a holder at the bottom of the reservoir—no tools or disassembly required.
  • Keurig sells official replacement filters, but third-party filters that fit your specific model work the same way and often cost less.

What you need before you start

Gather a replacement filter cartridge that matches your Keurig model. Keurig makes filters for different machine sizes—the standard cartridge fits most home brewers, but larger commercial models use a different size. Check your machine's manual or the Keurig website to confirm which cartridge number you need. You can also look at the filter holder inside your reservoir; it usually has the cartridge size printed on it.

You'll also need a cup or bowl of water for soaking the new filter. Tap water works fine. Have a clean, dry towel nearby to wipe your hands after the job. That's all you need—no screwdrivers, no special tools.

How to remove the old filter cartridge

Unplug your Keurig and let it sit for a few minutes if you've just used it. Open the water reservoir by lifting the lid or pulling it straight out, depending on your model. Look at the bottom of the reservoir; you'll see a plastic holder with the old filter cartridge inside it. The cartridge is a small tube, usually white or gray, about three inches long.

Grip the cartridge by the top and pull it straight out. It should come free with gentle pressure—don't twist or force it. If it feels stuck, run warm water around the holder for a few seconds to loosen any mineral buildup, then try again. Once the old cartridge is out, rinse the plastic holder under running water to remove any loose sediment or debris.

Prepare and install the new filter

Fill a cup with tap water and place the new filter cartridge inside it. Let it soak for 15 minutes. This step is essential—soaking activates the filter media and removes air pockets that would otherwise block water flow. While you wait, you can rinse the reservoir itself under running water to remove any dust or particles.

After 15 minutes, remove the cartridge from the water and slide it into the holder at the bottom of the reservoir. Push it straight down until it sits flush with the holder—you should hear or feel a small click when it's seated properly. The cartridge should not wiggle or come loose. If it does, pull it out and try again, making sure it's aligned with the holder opening.

Fill the reservoir and run water through the machine

Fill the reservoir with fresh water and place it back in the machine. Plug the Keurig back in and let it run through a full brew cycle without a K-Cup inserted—just let the hot water flow into the sink or a cup. This flushes out any loose filter material and ensures the new cartridge is working. The first cup of water may taste slightly different or look slightly cloudy; this is normal and will clear after one or two more brew cycles.

If water doesn't flow at all, the filter may not be seated properly. Unplug the machine, remove the reservoir, and check that the cartridge is pushed all the way down into the holder. If water flows very slowly, the filter may not have soaked long enough. Remove it, soak it for another 10 minutes, and reinstall it.

When to replace the filter and what to watch for

Mark your calendar for two months from the installation date, or set a phone reminder. Even if your machine seems to be working fine, replacing the filter on schedule keeps mineral buildup from damaging the heating element and pump. If you live in an area with hard water or use your Keurig multiple times a day, you may need to replace the filter every four to six weeks instead.

Watch for these signs that a filter needs replacement sooner: water flows noticeably slower than usual, the machine takes longer to heat up, or your coffee tastes like tap water or has a bitter edge. Any of these means minerals or sediment are building up inside the machine, and a fresh filter will restore performance.

Choosing between Keurig and third-party filters

Keurig sells official replacement cartridges under the brand name, and they work reliably. However, third-party filters made by other manufacturers fit the same holder and perform the same job—they catch sediment and chlorine just as well. Third-party filters often cost 30 to 50 percent less than official Keurig cartridges. The trade-off is that Keurig guarantees their own filters will work with their machines, while third-party filters vary in quality depending on the maker.

If you choose a third-party filter, check the product listing to confirm it fits your specific Keurig model number. Some filters are made for standard home machines, while others are designed for larger or commercial models. Reading customer reviews on the product page will tell you whether other users had good results with that particular brand.

Frequently Asked Questions

Can I use my Keurig without a water filter?

Yes, the machine will work without a filter cartridge, but mineral buildup will accumulate inside the heating element and pump much faster. Your coffee may taste like tap water, and the machine may eventually stop heating water properly or stop dispensing altogether. Using a filter extends the life of your machine by years.

What happens if I don't soak the new filter before installing it?

The machine will not dispense water, or water will flow extremely slowly. The soaking step removes air from the filter material and activates it. If you install a dry filter and nothing comes out, remove it, soak it for 15 minutes, and reinstall it.

How do I know which filter size my Keurig needs?

Check your machine's manual or look inside the water reservoir at the bottom—the filter holder usually has the cartridge size printed on it. You can also search your Keurig model number on the Keurig website, which will show you the correct filter. Most home machines use the standard cartridge, but larger brewers use a different size.

Can I clean and reuse the old filter instead of replacing it?

No. The filter cartridge contains activated carbon and mesh that wear out over time. Rinsing it extends its life by a few days, but it cannot be fully restored. Replacement cartridges are inexpensive enough that reusing an old filter is not worth the risk of mineral buildup in your machine.

Why does my coffee taste bad even after I replaced the filter?

The filter removes sediment and chlorine, but it does not affect the taste of your beans or water quality beyond that. If your coffee still tastes off, check that your beans are fresh, your machine is clean inside, and you're using the right water temperature for your brew strength. You can also try running a cleaning cycle with a Keurig descaling solution to remove mineral deposits from inside the machine.