Why Is My Coffee Maker Overflowing The Grounds Basket?

Have you ever been in a rush to get your morning cup of coffee… only to realize you have an overflowing grounds basket? Which means NO COFFEE and a GIANT MESS all over your kitchen counter.

Let’s explore the top 5 reasons why your coffee maker has an overflowing grounds basket. Then we’ll learn how to make sure it NEVER happens again.

Reason 1 – Too Much Ground Coffee

a Mr Coffee machine too full of ground coffee

It’s simple but worth thinking about. If the basket is too full of coffee grounds, then water can’t flow through the filter fast enough. And then you get a mix of coffee grounds and water overflowing from the grounds basket.

Not to mention you’ll get weak or even bitter coffee. Yuck!

We suggest using around 2 tablespoons of ground coffee for every 6 ounces (0.75 cups) of water. Make sure that there’s still room at the top of the grounds basket.

Another tip: try to level the coffee grounds with a spoon or your finger too.

Reason 2 – Coffee Grounds Are Wrong Grind Size

We’re guilty of this too: buying ground coffee without thinking about the grind size.

One easy solution is to find the best coffee grinder that lets you pick grind size. Then you can match based on your coffee maker. For example:

  • drip coffee makers work best with a medium grind or coarser grind
  • espresso coffee makers work best with a fine grind

Or you can check your coffee maker’s instructions and buy pre-ground coffee that matches their suggestion.

the brew basket should look something like this for a drip coffee machine

Reason 3 – Clogged Filter

This usually happens with reusable coffee filters. Make sure that you’re cleaning the coffee filter often, which means a minimum of washing with hot water after every use. Replace it if cleaning doesn’t get rid of clogs.

rinse your coffee filter after each use to prevent clogs

Even for a paper filter, you should rinse them with hot water before placing them into the filter basket. This gets rid of papery taste and also helps water flow when brewing.

Make sure you’re only using one filter. And that it’s opened completely + put in the exact right position.

Reason 4 – Too Much Water in the Water Tank

This one isn’t really your grounds basket overflowing. It’s more like water overflowing from your water tank into the grounds basket… and then your grounds basket overflows too!

Make sure you’re only using as much water as you need. And empty the water reservoir after every time you brew coffee.

This way you’ll prevent overflowing AND make sure you get delicious, fresh coffee.

Reason 5 – You Need to Deep Clean Your Coffee Maker

If you try to address the top 4 reasons and nothing works… then it’s time to try deep cleaning!

Brewing fresh coffee causes oils, minerals, and lots of coffee particles to get stuck everywhere in your coffee maker. This causes a slower brewing cycle. And it might even contaminate your coffee with used coffee grounds that might have gone bad.

Check out our simple monthly method to deep clean your coffee maker in 4 easy steps.

You can also see our 4 tips to prevent a coffee maker from leaking – those tips have a lot of overlap with fixing an overflowing grounds basket.

Frequently Asked Questions (FAQs)

Q: I have a specific coffee maker brand, what should I do?

First, you can check out our tips for different coffee brands’ coffee makers. We noticed that people online will usually think they have an overflowing grounds basket. But there’s actually a different area making their coffee maker overflowing.

Q: How can I tell if the coffee filter or grind size is the problem?

Check your filter basket right at the end of the brewing cycle. Look inside the brew basket and if you see:

  • Wet and clumpy coffee grinds (especially if there’s still water on top after waiting a while): the filter is likely clogged
  • The bottom of the coffee grounds are dry and powdery: the grind size is likely the issue

Q: How often should I replace a paper coffee filter?

Use new paper coffee filters every time you start the brewing process. Try to buy paper filters that cost a few cents per filter.

That way they’re cheap enough that you don’t feel pressured to reuse them.

If you do reuse paper coffee filters then you risk:

  • the filter paper getting clogged with remaining coffee grounds – which increases the chance of coffee maker overflow
  • the coffee filter collapsing or tearing apart – which means weaker coffee

Q: How often should I replace a reusable coffee filter?

This question can depend on whether you have a metal, cloth, or ceramic coffee filter.

Through wear and tear, the coffee filter’s shape can change which makes it easier for clogs to occur. And then the clogs cause coffee maker overflows.

Generally though, you can expect a metal or ceramic coffee filter to last several years. Make sure to rinse your reusable coffee filter and filter basket after every brewing cycle.


Don’t worry if your coffee maker is overflowing the grounds basket. There are a few reasons that are super easy to check:

  • Too much coffee grounds
  • Too coarsely or too finely ground coffee (not correct grind size for your coffee maker type)
  • A clogged, reusable filter

You can prevent a coffee maker overflow with a few other simple steps:

  • Prevent filter collapse from happening
  • Regular cleaning every 1-2 months to get rid of mineral deposits, coffee oils, and other leftover particles

Don’t be afraid to check out your coffee maker’s instruction manual too. Overflowing coffee makers can be annoying, but we’re sure our tips plus official guidance from the coffee maker company will get you through any coffee maker overflowing issues!

Bryan Han

By day, Bryan is a software engineer with experience at startups and top software companies. By night, he runs and writes for My Kitchen Sensei. Bryan is especially proud of his cheap excursions to cheap Michelin rated restaurants throughout Asia and in Hong Kong during his exchange there. His favorites include nitro-cold brew coffee and steak.

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