By purchasing a good thermos, you can make your life easier and more comfortable. Most people think that thermoses are necessary only for people who like camping or traveling, but it is not the total truth. 

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This article is for you if you want to learn more about thermoses and how you can use them. Here we will discuss how thermoses work, how you can choose the right one, and how you can use it in your daily life. 

What Is a Coffee Thermos

If we try to describe thermos most simply, it is a bottle or any other container with a double-walled tank inside. There is a vacuum between those two walls that helps to keep the heat inside a thermos. 

Air can transfer heat really fast and as there is no air between the walls, there is nothing that can transfer that heat out of the container. That is why your thermos can keep your cold drinks cold and hot beverages can stay hot. 

Benefits Of Using A Coffee Thermos

Perfect for Outdoors

Thermos is a perfect way to take your drink with you wherever you want. They are light-weight and easy to carry around. A good thermos can keep your drink hot for many hours and prevent spills. You can take it with you to enjoy your fresh coffee while going to work, walking around the city, hiking, or traveling. 

Shaped to Suit Your Needs

Nowadays, thermoses have different designs and shapes, so you can easily find the one that suits your needs and preferences. There are thermoses of different sizes, so you can get the one that fits in your bag or choose the option with a handle or with some band so you can attach it to your backpack.


As we said before, there is a variety of thermoses. They differ not only in size and design but also in types of delivery systems. Some options allow you to drink right from it and those with caps that can be used as separate cups. It would be best if you decided, which is more convenient for you.

Variety of Capacities

You can choose the capacity of your thermos depending on your needs. There are small ones that are of the size of a regular cup, bigger ones, and even huge options that can carry several liters of your favorite drink or the world’s best coffee cocktails.


A good thermos itself is not really cheap; however, it can save you lots of money. Instead of buying your coffee at coffee shops around your city, you can brew as much coffee as you need, pour it into your thermos, and carry it anywhere you want—a great way to save hundreds of dollars.

How Does a Coffee Thermos Work

How Does a Coffee Thermos Work

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There is a common misunderstanding that thermoses are used only to keep drinks hot. However, it is not a complete truth. The point is that thermoses are used to reduce the heat flow between the environment inside the thermos and the outside of it. 

The point is that heat flow not only causes heat loss but heat gain as well. It means that a thermos keeps your hot coffee hot and your cold beverages cold.

Pros and Cons of Using a Coffee Thermos


  • It is a convenient way to take your favorite drink with you anywhere.
  • A thermos can save you lots of money as you do not need to buy coffee in coffee shops.
  • It can keep your drinks either hot or cold for a long time.
  • Thermoses are easy to carry around.


  • A high-quality thermos can be quite expensive.
  • A bad thermos can spill coffee in your bag.
  • Cheap thermoses can lose its ability to keep your drinks hot and cold pretty fast.
  • You need to clean it well after each usage.

How to Choose the Best Coffee Thermos

Size and Volume

The size and volume of your thermos are critical. You need to decide if you will use it on your own or want to share your coffee with others. Also, it would be best if you considered how much coffee you drink. For example, it can match the size and capacity of different Keurig models.

If you like drinking a lot of coffee and sharing it with others, a big thermos will be perfect for you. However, it would help if you remembered that it would be heavy as well. 

In case you need one or two cups of coffee per day, smaller options will help exactly what you need. Moreover, it is easy to place in your bag and carry around.


When it comes to high-quality thermoses, their inner part is usually made of glass or stainless steel. These materials are great for storing coffee. Simultaneously, plastic inner parts covered with reflecting coating aren’t an option as they are not safe for your health. Moreover, such thermoses will hardly be able to maintain the right temperature of your drinks.


Stainless steel thermoses have double-wall construction that is the best for keeping the temperature of your drinks. Properly made thermos can keep your drinks hot or cold for many hours.

Design and Other Features 

You may think that the design and extra features of your thermos are not so important. However, it may have a significant impact on your experience. If you pay attention to its shape, lid, and extra features, it may make your life much easier. 

Delivery System 

Coffee Thermos Delivery System

Two traditional delivery systems are used for thermoses. The first one is an air-locking lid. One other option is an exterior lid that also can be used as a cup. Both these types of lids are leakproof as they are equipped with special rubber seals that safely keep liquids inside your thermos. It is an essential thing to keep in mind as a properly sealed thermos can not only guarantee the protection of the belongings in your bag from your coffee but also protect you from getting burnt with hot coffee.

Moreover, there is one more type of lids, but it is mainly used for travel mugs and not for classic thermoses. It is often called Contigo’s SnapSeal lid that was created by the Contigo company. Nowadays, numerous companies widely use it and despite some variations, the whole concept is the same. If you want to get a thermos with such a lid, make sure it is properly sealed if you want to avoid spills.

The type of lids is significant as it impacts how easy you can enjoy your coffee without spilling it yourself. For example, silicon lids are very secure but rather uncomfortable when it comes to drinking, so be attentive when making your final choice. 

Leak and Spill Proof Measures

It is evident that when choosing a thermos, you need to be sure that it will not make a mess inside your bag and ruin your things. That is the main reason why you need to pay special attention to how well it is sealed. When choosing cheap and low-quality options, your thermos is likely tilted each time it will leak some liquid. 

Moreover, if the lead is not properly sealed, your drink may lose its required temperature faster, which means that the whole thermos loses its main purpose. It means that you should pay attention to the type of lead, the material it is made from, the way it is sealed. Of course, the best thing to do is avoid cheap thermoses as they are usually made of low-quality materials.

Temperature Retaining 

When it comes to thermoses, heat retention is surely one of the most important things to consider. In simple words, heat retention is the period how long your thermos can keep your drink hot or cold. Most thermoses can keep the temperature of your drink for about 4-5 hours, but there are even options that can keep your coffee hot for 12-15 hours. When it comes to cold drinks, the time should be even longer. By the way, if you are looking for a way to keep your coffee hot, an electric hot plate is a great mug warmer.


It is essential to keep your thermos clean as some drinks may leave heavy stains. However, due to its bottle-like shape, it can be hard to clean it properly, especially ina dishwasher. 

Some thermoses are designed in a way so they can be cleaned in a dishwasher. You can also find options with a non-stick coating inside, which makes cleaning easier as there are fewer stains. 

Finally, it is a good idea to choose a thermos that can be easily disassembled, making cleaning much easier and faster. 

How to Prepare a Thermos for Your Coffee

How to Prepare a Thermos for Your Coffee

After purchasing your perfect thermos, it is time to think about how to make it keep your drink hot longer. There is a process that is known as thermos “charging” that will help you make your thermos more effective and long-lasting. The process is straightforward and does not require any special equipment or substances, so you can easily do it at home on your own. You’ve had a coffee grinding technique? Just grind your coffee and brew it while charging your thermos. 

Step 1 – Fill it with hot water

First of all, you need to boil enough water to fill your thermos. After it, pour it inside your thermos and cover it with the lid properly. 

Step 2 – Let it sit

After the lid is covered well, leave your thermos for several minutes and let it sit. It will let you preheat the thermos and make it keep your drink hot for longer. 

Step 3 – Prepare your drink

While your thermos is charging, it is time to prepare your drink of choice. Prefer coffee? Take your time and brew enough coffee to fill the thermos using one of the coffee measurement guides. By the way, you can get the best coffee canister to keep your beans fresh.

Step 4 – Pour out the water

As soon as you brewed your coffee and added sugar, creamer, and other ingredients if necessary, it is time to pour out the water from your thermos. An interesting fact – coffee creamer last longer than regular milk.

Step 5 – Fill it with hot coffee

Finally, it is time to pour your coffee into your thermos. Just pour your drink inside but be careful not to spill it and get burnt. 

Step 6 – Pack and go

Close the lid tightly and make sure your coffee will not spill inside your bag. Pack the thermos and you are ready to go. 


How to Clean a Coffee Thermos

A coffee thermos is a perfect option for people who want to keep their beverages hot or cold throughout the day. Moreover, it is a great way to take your drink with you anywhere. However, a thermos has one big disadvantage – it is tough to clean due to its shape. Also, you need to pay attention to the special features of a coffee scale.

Nevertheless, it does not mean it is impossible to clean. There are several pretty easy hacks and methods that you can use to keep your thermos clean. They are basic and almost the same as Cuisinart coffee machine deep cleaning methods. Below, you can find various methods for thermos cleaning that you can use at home. We made sure to provide you with all the information you need, so choose the one you like most and follow our step-by-step guide. 

Salt and Ice Method


  • ice (crushed is better )
  • 2-3 tbsp of salt

Step 1 – Put the ice in your thermos

Take ice cubes or crushed ice and place it inside your thermos. It is enough to fill one-quarter of the volume with ice. 

Step 2 – Add salt

Take salt; it is better to use a large-grain one, and add 2 or 3 tablespoons inside the thermos. Just make sure to do it as fast as possible and add salt on top of the ice. 

Step 3 – Shake, shake, shake

Close the lid tightly and pretend to be a bartender – shake the thermos really well. Ice and salt will rub your thermos’ insides and exfoliate all stains without damaging the walls. 

Step 4 – Rinsing

Open the thermos and empty it. After it, rinse the thermos with some cold water until there are no remains of salt inside of it and let it dry properly.

Vinegar and Baking Soda Method


  • 4oz of white vinegar
  • 1 tbsp of baking soda
  • hot water

Step 1 – Add vinegar

Pour vinegar inside your thermos and add baking soda there. It is better to shake soda over vinegar so the chemical reaction can occur gradually and clean the insides of your thermos. 

Step 2 – Pour some hot water

Wait until there is no fuzzing inside the thermos and add hot water. Make sure to fill the thermos to its full capacity. 

Step 3 – Wait for 10 minutes

Do not cover the thermos with the lid as the reaction between vinegar and soda is very strong. Just leave the mixture inside the thermos for about 10 minutes.

Step 4 – Brush

After 10 minutes pass, it is time to use a bottle brush and remove the remaining stains from your thermos’ inside walls. 

Step 5 – Rinse and wipe

Finally, you need to empty the thermos and rinse it carefully. The best way to clean the thermos from the vinegar is to use some warm water. As soon as the thermos is completely clean, wipe it with a soft cloth and let it dry completely. By the way, you can also use vinegar for Bunn coffee brewer cleaning.

Dishwasher Powder Method


  • 1 tbsp of dishwasher powder
  • hot water

Step 1 – Add dishwasher powder

Put the dishwasher powder inside the thermos. Make sure to use the powder as it has better exfoliating properties than liquid. 

Step 2 – Shake, shake, shake

Add hot water and clover the thermos with the lid, and shake it briefly.

Step 3 – Let it soak for several hours

After it, open the lid, fill, add water to fill the thermos to its maximum capacity, and leave it to soak for several hours. This time there is no need to cover it with the lid.

Step 4 – Scrub and rinse

Pour out half of the liquid and use a bottle brush to scrub off the remaining stains. After it, you need to empty the thermos, rinse it well with some warm water, and leave it completely dry.


Dishwasher Denture Tablets Method


  • 1-2 denture tablets
  • hot water

Step 1 – Let it soak

Fill your thermos halfway up with warm water and let it soak for a little and, after it, swish the thermos to make sure all the walls are wet.

Step 2 – Add denture tablets 

Keep your thermos inside the sink as the reaction can be really strong and put 1 or 2 denture tablets inside it. 

Step 3 – Let it sit

Do not cover the thermos with the lid and let it sit for about thirty minutes. 

Step 4 – Scrub

After it, use a bottle brush to scrub off the remaining stains and pour the liquid into the sink. 

Step 5 – Rinse and dry

Use some warm water to rinse the thermos properly to ensure there are no remains of a cleaner, and let it dry completely without the lid. 

Does More Spending Mean More Quality

Cheap thermoses are usually made of cheap, low-quality materials. First of all, they can be dangerous to your health. Also, cheap thermoses will not keep the temperature of your drinks. Moreover, they may be unproperly sealed and cause a real mess inside your bag. That is why it is better to avoid cheap thermoses.

Actually, the conclusion is straightforward. When it comes to thermoses, more spending indeed means more quality. It does not mean you need to buy the most expensive thermos, but the cheapest one is not an option for sure. Choose double-walled thermoses made of stainless steel with a properly sealed lid. 

Do’s and Don’ts With a Coffee Thermos


  • Choose a high-quality thermos.
  • Make sure it is double-walled and sealed well.
  • Clean it well after each use.
  • Follow the manufacturer’s instructions to make it last longer.
  • Close the lid well to avoid spills and mess.


  • Do not damage your thermos.
  • Never use cleaners that may damage the insides of your thermos.
  • Never leave it dirty.
  • Do not cover it with the lid if it is wet.

FAQ About Coffee Thermoses

FAQ About Coffee Thermoses

How do you get the smell out of a coffee thermos?

If there is a strange or unpleasant smell inside your thermos, you can clean it with vinegar and water or any other method described in our article. 

How do you get coffee stains out of a thermos?

There is a variety of methods you can use to remove stains from your thermos. You can use soda, vinegar, salt and ice, dishwasher powder, and tablets. All of them are great for removing stains.

Can you clean a thermos with bleach?

Absolutely not! Bleachers contain agents that can be really hazardous for your health and cannot be used for cleaning any dishes or food/beverage storage containers. There are lots of other effective methods to clean your thermos. Moreover, it is always better to check instructions to find the best way to clean a thermos. 

How long does a thermos keep coffee hot?

It depends on your thermos, but usually, if you pour boiling water into a preheated thermos, it will stay hot for about 6 hours and warm for almost 12. Larger thermoses tend to keep your drinks hot for a longer period of time.

Why does my thermos not stay hot?

It may happen because the seal was damaged with excessive heat or strong cleaner. Some seals can be used with hot water but not boiling one. Make sure to read the instructions carefully to learn more about your thermos’ features and the proper way to use it. 


Thermoses are absolutely great as they can keep your drinks hot for a long time. It is a great opportunity to take your coffee with you for a walk, a trip, work, hiking. Actually, anywhere. In such away, you can enjoy your favorite coffee any time you want and save lots of money as you don’t need to buy coffee at coffee shops. 

If you want to learn more about coffee, we have lots of useful guides for you. For example, do you know that smoke suppression is important when roasting coffee? Take your time and learn more about your favorite drink. 

Photos from: efired /, belchonock /, AlexLipa /, doble.dphoto / and kirs-ua /

Love drinking great coffee? If you want a tasty, freshly roasted bean you can buy online, try something from LifeBoost and thank me later. Click here to check it out and save 50%.