How Long Can Coffee Sit Out?

By: Ivan Montes
Last Updated:

How long can coffee sit out? If enjoyed like most of the people we know, with milk and sugar, 2 hours is the sweet spot.

For people across the world, coffee holds an important role in their daily routines. It serves as a vital “pick-me-up” in the morning, an energizer throughout the day, and a warm comfort on chilly evenings. However, what happens when this treasured beverage is left out for an extended period? 

Leaving coffee to sit out for long periods of time can let bacteria grow, leading to it being spoiled and causing sickness if digested.

Here is a guideline of what is to come in this article:

Factors that can affect coffee “Life”

Unfortunately, coffee is not invincible like mom and dad, so it is prone to spoiling considering a few factors.


The temperature at which coffee is stored has a great influence on bacterial growth. Bacteria tend to grow in environments that are both warm and humid and can swiftly reproduce in high temperatures. 

When coffee is left out at room temperature, it generates an atmosphere that is great for bacterial growth. 

Coffee can be stored in either the refrigerator or freezer, by doing so, it can lower bacteria growth. 

However, it is important to know that repetitive fluctuations in coffee temperatures caused by taking it in and out of the refrigerator or freezer can make bacteria grow.

Milk and sugar

There are people that enjoy black coffee, but there are others that prefer to alter its natural state to a sweet taste with sugar and also milk/cream.

Sugar and dairy in coffee can have a significant impact on the duration for which it can be left out before becoming unsafe for consumption. Both sugar and dairy hold a significant quantity of moisture, making them viable sources for bacterial growth.

When adding sugar to coffee, a risk for bacterial growth is generated.  Sugar contains glucose, which bacteria use to create energy. As a result, coffee mixed with sugar is more prone to spoiling at a faster pace than plain black coffee.

The presence of dairy in coffee can also expedite bacterial growth. Milk and cream, for instance, hold a good amount of proteins and fats that bacteria can metabolize and consume as fuel. This course of action can result in spoilage and the emergence of potential bacteria in coffee left out for too long.

To prevent coffee from going bad, coffee that contains milk or sugar must be consumed within 2 hours of being brewed to reduce the risk of bacterial growth.

Tips for storing and reheating coffee

Let’s explore some options for storing and reheating coffee to extend its life.

Storing containers

Properly storing your coffee can make a big difference in its taste and freshness.

1. Airtight: Oxygen can make coffee go stale, so look for containers with tight-fitting lids or seals to keep air out.

2. Lightproof container: Coffee can also lose flavor when exposed to light, so pick a container that is opaque or has a lightproof coating.

3. Right size: Too much air exposure can spoil coffee, so choose a container that’s the right size for your needs. 

4. Right material: Coffee containers come in different materials, such as glass, ceramic, and stainless steel. Glass and ceramic can look nice, but might not be airtight, unlike stainless steel.

5. Right location: Store your container in a cool, dry place, where it’s away from heat, light, and moisture.


We won’t blame you for trying to revive the flavor of your coffee, but to help you out, here are some safety tips for reheating coffee:

1. Microwave: The microwave is the quickest way to reheat coffee. Heat it up in a microwave-safe mug. Give it a stir and check the temperature before drinking.

2. Stovetop: Reheating coffee on the stovetop takes a little more time, but it provides a more even and controlled heating process. 

3. French press: You can also use a French press to reheat and brew coffee. Pour the cold coffee into the French press and heat the water separately on the stove. Once the water is heated, pour it into the French press and stir. 

4. Coffee maker: Some coffee makers come with a warming plate that can keep coffee warm for several hours. By reviving coffee using a coffee maker, pour the coffee into the machine and let it run through the brewing process. This method may take longer, but it’s a convenient way to reheat coffee without any extra effort.

Remember to never reheat coffee more than once and to avoid overheating it, which can cause it to become bitter. By using these methods, you can safely and easily reheat your coffee and enjoy a delicious cup every time.

Don’t forget

Coffee is considered by some “liquid gold” so always enjoy it in moderation and don’t forget to share it with the world.

What now?

Now that you know how long coffee can sit out, make sure you read our article on How many scoops of coffee per cup?

Photo of author


Ivan Montes

Ivan Montes is a Business Management Engineer that enjoys spending time with family and researching how to improve quality of life with quality products.

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