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How Long Can You Keep a Coffee Maker On

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Updated August 25, 2022

The question, “How long can you keep a coffee maker on?” has a simple answer. Unfortunately, leftover coffee loses quality quickly, even if you have the best coffee maker. It can also be unsafe to consume depending on how long your leftover coffee has been out. Keep reading to find out more.


  • Your cup of coffee in the morning is most enjoyable directly after the brewing cycle finishes; it loses quality quickly within the first few hours after brewing.
  • Keeping coffee hot by leaving the pot on is tempting, but doing so for an extended period, especially near flammable objects, is a recipe for disaster.
  • If it’s not possible to drink your coffee in a relatively short time, it’s best to make a new, hot brew and dump out any remaining cups of coffee rather than leave your pot on to keep coffee hot.

Is it Safe to Keep Coffee Warm in the Pot?

Leftover coffee presents a problem on multiple fronts. Bacterial species thrive in leftover coffee, for example. You also have to worry about losing the pleasant flavor you’ve worked to cultivate through your brew technique.

Speaking of brew technique, understanding how to craft perfect coffee begins with using the proper temperature range. If you’re curious, we have an article explaining just how hot does coffee get in a coffee maker that explains everything about the temperature range. To ensure your coffee stays nice and hot for when you want that second or third cup, you may want to check out how to keep coffee hot in the coffee maker.

Insider Tip

Making the perfect cup of coffee is an art, so don’t be afraid to experiment with different coffee brewing methods and techniques.

The Risks of Keeping Coffee Warm

The best-tasting coffee is fresh coffee. Coffee lovers across the board will confirm that nothing beats a fresh cup of coffee. While that delicious coffee taste is important, it doesn’t last more than a few hours after the brew cycle is done. It’s also not the only reason to throw away day-old coffee.

You’ll also want to answer the question, “How long should a coffee maker take to make coffee?” so you can factor that time into your morning routine. Alternatively, you can look into how to use a smart plug with your coffee maker to start your machine while you get ready.

Bitter Taste in Leftover Coffee

A lot goes into extracting the perfect pot of coffee. Grind size, brewing time, brewing temperature, and more help determine a pleasant flavor. While black coffee is stronger than brew coffee mixed drinks, it shouldn’t be overly bitter. And if you love a strong cup, you can learn how the strong setting on a coffee maker works. Because coffee starts to degrade quickly once brewed, day-old coffee will always taste terrible.

And it’s not just time that ruins the flavor, either. By leaving your glass carafe of coffee on the warming plate, you’re likely to overheat it, which will essentially burn your brew. A better option would be to invest in a thermal carafe to keep it warm as long as you plan to drink it within a few hours. Thankfully, most new coffee machines come with an auto shut-off feature to help prevent burnt coffee. Otherwise, if you want to preserve the flavor, there’s nothing to do except make smaller brew sizes and throw out any leftover coffee that’s more than a few hours old.

Chance for Growth of Bacteria

Keeping coffee fresh is essential for more than just your taste buds. Coffee that’s been sitting around carries many risks, and this is especially true if you prefer to have coffee with milk. Bacteria and mold will quickly colonize a pot of old coffee. The best way to avoid bacterial growth is to throw out old coffee and clean your coffee maker. Use a fresh water and vinegar solution during your cleaning cycles to get the best results.


If you struggle with remembering to turn off your coffee brewer and your model doesn’t have an automatic shut-off feature, consider switching to using coffee powder instead, or you could eventually start a fire.


When should I replace my coffee maker?

The average lifespan of a coffee maker is about five years, but high-end models may last ten or more. But while modern coffee makers don’t need to be replaced as often, there will come a time when your morning coffee leaves something to be desired. This can be due to the appliance not producing hot coffee anymore, finding worrisome amounts of ground coffee in your morning cup, and more.

Does pre-ground coffee go bad?

While coffee grounds and roasted coffee beans don’t “go bad” the same way as other products, they will go stale. In terms of flavor, this spells disaster. You can expect pre-ground coffee to last about three months once opened, but only if it’s stored properly. Whole beans will last much longer. Keep all whole or ground beans in an airtight container to avoid stale coffee.

Is it okay to make coffee with tap water?

It’s OK to make coffee with tap water. The only issue is that build-up from minerals may form in your water reservoirs. Just make sure you use white vinegar and hot water to clean out your coffee machines regularly.

How can I avoid leaving my coffee pot on?

There are a few ways to remind yourself of the hot pot of coffee you need to turn off. Setting the alarm on your phone is an excellent method. Another is to invest in a model with an automatic button for shut-off.

STAT: 400 million cups of coffee are enjoyed each day in America. (source)

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