Anyone who enjoys coffee on the go knows the numerous challenges and thus the requirements for the perfect travel mug. These range from leak-proof and drip-proof to temperature-resistant and dishwasher-safe, as well as easy handling. Last but not least, the coffee should also show its true character and taste good after a certain time, and not be overshadowed by metallic notes. In search of the perfect thermos mug, travel mug, or to-go cup, we tested 12 different mugs.
The Test Criteria
The evaluation of the to-go cups was divided into taste and technical criteria. These have been refined through community feedback and working with the travel mugs.
We focused on the following criteria:
1. The influence of the container on taste
2. Tactile sensation
3. The drinking experience
We tested all 12 to-go cups over a period of two hours. We tasted them 10 minutes after pouring, after 30 minutes, after one hour, and after two hours.
Taste and Mouthfeel
We evaluated both the taste – divided into flavor and off-taste (foreign odor) – and the tactile sensation, divided into mouthfeel and aftertaste. We also recorded how pleasant it was to drink from each cup.
Since some of the containers are also intended for enjoyment without a drinking spout, such as the Loveramics Nomad or the KeepCup, we decided to taste all to-go cups both with and without a drinking spout. This led to some models scoring lower in the 'without drinking spout' category, as they are not designed for it. Conversely, there were also cases where the drinking spout significantly impaired the drinking experience.
Is the temperature constant?
Furthermore, we measured the temperature in the container over 2.5 hours. While this does not affect the overall rating, it could influence the purchasing decision depending on individual preferences.
For the test, we poured 200 ml of water with an initial temperature of 94°C into all thermos mugs and immediately measured the temperature. Surprisingly, all test objects lost between 7 and 18 degrees within the first few seconds. It is important to note that none of the mugs were preheated.
The thermos mugs specifically designed for coffee fortunately performed best in terms of temperature consistency over time. The Kinto Travel Tumbler, Carter Fellow Move, and the Iris Go were still over 62 degrees hot after two hours. Our Kaffeemacher mug and the FLSK also performed well in the upper midfield.
As expected, the more cup-like products could not retain the temperature for long. However, it should be noted that these are intended more for quick drinking and not for longer journeys.
The Tested Travel Mugs
Our 12 test mugs can be broadly divided into two groups.
- Leak-proof To-Go Cups
- Non-leak-proof To-Go Cups
This division has no influence on taste and tactile sensation, but it helps to select a suitable thermos mug according to personal needs. The following table summarizes the most important basic data.
Leak-proof To-Go Cups
Emsa Travel Mug Classic (360ml), CHF 23.20 / € 24.52
The Emsa Travel Mug Classic looks like a typical all-purpose stainless steel thermos mug and won't win any design awards. The outside of the mug is covered with a rubber coating that retains temperature well. The mug is easily opened by pressing a button (Quick-Press) in the middle of the lid, but this feels a bit unusual to me. Due to the twist-off cap and the Quick-Press, it is 100% leak-proof and its shape is also ideal for longer car journeys. The thermos mug can be easily disassembled and is dishwasher safe.
To drink from the Emsa Travel Mug Classic, you have to tilt it extremely. With hot liquid, this causes fear of burning. And some drops may remain in the crevice next to the very high drinking rim.
Sensorially as well as in terms of temperature, the thermos mug is in the middle range. With 85.35°C immediately after pouring, it belongs to the upper half of the tested objects. After 2.5 hours, it still holds 53.15°C, placing it in the middle range. This is actually surprising, as one might have expected better insulation due to its tight seal.
In terms of taste, it is not entirely convincing and ranks in the last third. After just 30 minutes, a distinctly metallic taste emerges, and the coffee develops a harsh and scratchy aftertaste. To the Esma mug*.
Kaffeemacher Mug (250ml), CHF 29.90
Our Kaffeemacher mug from the brand Aladdin is dishwasher-safe and can be transported in a backpack without hesitation thanks to its double leak protection. The double-walled stainless steel provides good insulation and the durable powder coating ensures a firm grip. Due to its shape, the thermos mug is versatile and fits well not only in the car's cup holder but also in the bicycle's drink holder. The drinking opening of the mug is small and the closure does not exactly bring me joy.
Unfortunately, our mug did not perform very well in our comparison. While it also has its fans, sensorily it simply could not keep up with the best. In terms of temperature consistency, it is still among the top performers, doing quite well with 86.63°C directly after pouring and 56.85°C after 2.5 hours.
However, the mouthfeel and taste leave something to be desired, placing it in the lower half. The coffee in the thermos mug does not noticeably deteriorate over time, but it is only in the middle range from the start. To the KM mug
Iris Go (200ml), CHF 45.00 / € 45.00
The Iris Go surprises with an unusual look, because unlike all other thermos mugs in the test series, it does not have a removable lid. The closure nestles directly against the edge of the stainless steel when twisted open. To close it, the closure is simply twisted shut again.
Drinking from this soft rubber rim is very unusual for some of our test team. However, the coffee enjoyment from this large opening is very cup-like. A small disadvantage: when closing, a little coffee or milk sometimes remains on the closure, which can then drip into the bag or dry out.
We conducted the leak test without the separately available cover. According to the manufacturer, it is leak-proof even without a cover. However, in our test, a few drops leaked out, which is why we would not throw the Iris Go into a backpack, but only transport it upright.
The double-walled, vacuum-insulated stainless steel mug is 100% recyclable, which is a big plus in terms of sustainability. The aforementioned cover protects the closure from dirt, which is much more hygienic depending on the intended use of the mug.
With 84.48°C directly after pouring the coffee, the Iris Go is in the middle range of initial temperatures. Although the temperature still shows 62.11°C after 2.5 hours, making it the third hottest mug at the last measurement, this has less negative impact on taste and mouthfeel compared to others with this high temperature consistency. Although the coffee in the Iris Go also becomes flatter and more characterless over time, it shows less off-taste.
The Iris Go performed very well across all levels and wins our test series!
At the manufacturer's recommendation, we tested additional models for tightness. These are generally tight. However, with hot beverages, closing the lid can cause slight moisture on top, which can lead to a few drips. The additionally available lid prevents dripping into the bag.
After testing further models, we moved the mug to the "Leak-proof To-Go Cups" category.
FLSK Coffee Mug (350ml), CHF 39.00 / € 39.00
The bulky and two-time award-winning (German Design Award Special 2022, Green Product Award Winner 2022) FLSK coffee mug is pleasant to hold and has an elegant look. The security closure, the flip lid, seals the drinking opening on the one hand and can be fixed on the top of the lid on the other, so that it does not disturb when drinking. A vacuum layer between the stainless steel walls is intended to slow down heat leakage, while the copper coating additionally supports this effect.
With 84.67°C directly after pouring and 54°C after 2.5 hours, the thermos mug consistently remains in the middle range of all test products throughout the temperature measurements.
The small opening regulates the drinking flow but also holds back the foam of the milk. Without a lid, the mug offers a pleasant drinking experience, but with a lid and its small opening, it failed to convince us. Nevertheless, the flavor, texture, and aftertaste remained consistently good throughout the entire measurement period, ultimately earning the FLSK coffee mug third place.
Kinto Travel Tumbler (350ml), CHF 39.00 / € 37.50
The very elegant Kinto Travel Tumbler is made for coffee and tea and is a favorite of many coffee professionals and aesthetes. The test team immediately perceives it positively visually. Its unmistakable Japanese design convinces with minimalism and functionality. A divider holds back ice and herbs (for tea), while the drinking stopper additionally regulates the beverage flow.
The drinking stopper is an attachment for the stainless steel insulated mug and therefore does not take up space downwards, as is the case with the Fellow Carter Move, for example. This allows the mug to be filled to the top. When unscrewing the lid, the drinking stopper sometimes comes along, which is a bit awkward. Due to its slim shape, the Kinto Travel Tumbler fits perfectly even in small hands and fits into both bicycle and car cup holders.
This insulated mug also prevents heat transfer by means of a vacuum between two stainless steel walls. Of all the tested mugs, it loses the least temperature, still holding 65.89°C after 2.5 hours. However, this also means that it is very hot at the beginning, which can cause fear of burning.
However, sensorially, the thermos mug is (unfortunately) not convincing and therefore ends up in last place. On the one hand, we do not find the drinking sensation positive. The plastic rim feels uncomfortable, and the relationship between the diameter of the opening and the depth of the drinking rim means that the nose hits the upper edge. On the other hand, due to the prolonged heat exposure, the coffee quickly develops a metallic taste and, towards the end of the time, even a vegetable-like, herbal, harsh aftertaste.
To the Kinto Travel Mug at Kinto or Amazon*.
Fellow Carter Move (355ml), CHF 42.00 / € 45.00
The Fellow Carter Move Mug impresses with its clean design and was specially developed for coffee. The ceramic inlay is designed to prevent unpleasant odors, such as a metallic taste. Along with the Kinto Travel Tumbler, the Fellow Carter Move is one of our community's most popular travel mugs. The snap-in splash guard allows for comfortable "on the go" drinking despite the large opening and protects against splashing. Thanks to the twist-off cap, the mug is 100% leak-proof.
The Fellow Carter Move is double-walled vacuum insulated, preventing rapid heat and cold loss. Specifically, this means that although it loses 10°C directly after pouring and lands in eighth place with 83.83°C, it loses very little over time and keeps the drink hot for the second longest time at 65.3°C.
If only mouthfeel and taste are considered, without the drinking experience, the mug achieves rank 4 in the overall ranking. As with all thermos mugs, the quality of the coffee decreases somewhat over time, and a slight bitterness develops. Nevertheless, body and acidity remain pleasantly balanced. However, if the drinking experience is included in the evaluation, the Fellow Carter Move drops to eighth place. We all experience the metallic rim and the splash guard differently, but neither as good nor bad.
To Fellow Carter Move at Fellow or Amazon*.
Kaffeeform Weducer Cup (250ml), CHF 19.90 / € 15.88
The Weducer Cup presents itself as a sustainable alternative to conventional mugs and visually resembles a classic disposable to-go cup. The brown color may seem unusual and not very aesthetic at first glance. But this impression is relative, because the mug is made from recycled coffee grounds from Berlin cafés and roasteries, which also explains the color. In addition, no petroleum-based raw materials are used, which means the Kaffeeform team is taking a forward-looking approach. The Weducer Cup is light yet robust and features a disposable-like drinking spout and a leak-proof lid.
Due to the double outer shell, the drink stays tempered, but not hot. The Weducer Cup is therefore more suitable for short distances or quick consumption. Already after pouring, the temperature is only 80.3°C, placing it among the last in the measurements along with the Loveramics Nomad and the KeepCup. However, this does not have to be negative, as the drink is ready to drink quite quickly. It is therefore recommended to drink the coffee within the first few minutes after brewing, because at the last measurement the temperature was only 30.16°C.
Sensorially, the mug starts in the good midfield, but then drops to the last places after just 30 minutes. The coffee does not develop a metallic or other off-flavor, but it becomes flat, dull and dry over time.
To the Kaffeeform Weducer Cup.
Non-leak-proof Travel Mugs
Yeti Rumbler (296ml), CHF 23.00 / € 25.00
The Yeti Rumbler is a classic American stainless steel travel mug in the mid-price segment. According to the manufacturer, this version is ideal for espresso. The mug is comfortable to hold, as the metal is temperature-neutral and does not get hot, and features double-walled vacuum insulation. The MagSlider in the lid is a simple slider that, at least when new, moves easily and seals well. However, it is not leak-proof and is therefore more suitable for straight or slightly bumpy transport than for a backpack. Due to its features, it is a good companion for car journeys.
The Yeti Rumbler impresses with its insulation. It loses the least temperature directly after pouring 94°C hot water, still showing 87.43°C, which represents the smallest loss in the test. Even after 150 minutes, it still measures 59.18°C, placing it in the upper third regarding temperature consistency over the entire measurement period.
Drinking through the small opening is rather unfavorable for mixed drinks like cappuccino and flat white, as it retains all the milk foam. However, drinking without the lid is not recommended, as the edges of the mug are quite rough. Sensorially, the thermos mug performs well at first, but after about an hour it develops a musty, metallic off-taste. In addition, the coffee loses more and more aromas and becomes flat.
To the Yeti Rumbler at Amazon*.
Asubo Ultimate Mug (355ml), CHF 18.90 / € 17.70
This cup-like to-go cup appears multifunctional and suitable for outdoor use. I would love to drink soup from it. But: The Asobu Ultimate Mug is specifically made for coffee and clearly surprises sensorially. Without the lid, it feels like drinking from a normal cup. With the splash-proof slide-closure lid, the opening becomes significantly smaller, but the drinking experience remains surprisingly good.
The vacuum-insulated and copper-coated walls keep the temperature surprisingly high for a long time. This is even more surprising considering that while the sliding closure seals the opening, a lot of heat can still escape. Immediately after pouring, the mug loses 10°C and is in the middle range at 84.19°C. After 2.5 hours, the temperature is still 51.92°C, placing it in 8th position. Positions 9-12 show only 42.92°C or less after the same period.
The ceramic coating inside is intended to prevent the transfer of foreign odors. The coffee remains surprisingly dense and retains a certain structure throughout the entire test period. Up to the last tasting, it has no off-taste and is still sweet and balanced. The Asobu Ultimate Mug thus surprises all of us and lands in second place in our final ranking.
Loveramics Nomad (250ml), CHF 24.80 / €28.90
A beautiful double-walled porcelain cup in the style of Loveramics. But the rubber lid and the tiny opening are a flop and severely detract from the multi-sensory drinking experience. Besides the fact that hardly any liquid comes out of the small hole, the coffee takes on the taste of rubber within milliseconds. Without the lid, however, you have a completely different experience. Drinking directly from the cup is convincing both sensorially and visually across the board.
The Loveramics Nomad is also not intended for long journeys. Despite the double-walled porcelain, it lands in second to last place at 80.01°C immediately after pouring and reaches third to last place after 2.5 hours at 30.16°C.
Sensorially, it was an emotional rollercoaster. Together with the KeepCup, we rated the coffee from the Loveramic Nomad as best in terms of taste and mouthfeel immediately after pouring. And without the rubber lid, it provides a very pleasant drinking experience, which would put the cup in third place. However, if you drink with the lid, the rubber off-taste immediately masks the coffee flavor.
Loveramics Nomad in Switzerland at Kaffeezentrale.
Stanley Legendary Camp Mug (330ml), CHF 34.90 / €35.00
An incredibly trendy brand. It would be absolutely cool if this robust stainless steel camp mug, like the Asobu Ultimate Mug, were also fireproof. This way, they could serve for coffee in everyday life and be used for campfires in leisure time. Visually, it appears much more massive and less elegant compared to a Kinto Travel Tumbler or a Fellow Carter Move, and its look is more similar to the Asobu Ultimate Mug. We are not entirely convinced of how practical this lid is in everyday life. It is more of a splash guard or protection against spilling than a real lid, as it cannot be completely sealed.
Thanks to the double-walled vacuum insulation, the coffee also stays warm longer in this mug. Due to the aforementioned opening in the lid, the coffee cools down faster and is therefore not leak-proof. In the temperature measurement, the Stanley Legendary Camp Mug is at the lower end of the table both at the beginning with 83.04°C and at the end with 42.92°C.
In terms of taste, the mug cannot keep up either. Already directly after pouring, we see comments of metallic taste and slight bitterness. This does not improve over time, and thus the mug lands in 10th place in the overall ranking.
Stanley Legendary Cup on Amazon* or Stanley.
KeepCup (227ml), CHF 29.00 / €27.95
A beautiful glass cup with a refined cork band, available in various designs, colors, and sizes. Thanks to the cork band, the Keep Cup can be held well, although the glass naturally gets very hot. Unfortunately, the solid plastic lid detracts from the overall appearance. The cover protects against spilling but is not leak-proof.
The glass extracts a lot of heat from the coffee from the start, so it only registers 76.01°C at the first measurement, while the glass itself reaches 60.3°C and 46.2°C after 15 minutes, respectively. For comparison: thermal mugs like the Kinto Travel Tumbler only show an outer temperature of about 25°C after 15 minutes.
With the KeepCup, drinking through the small plastic opening is neither pleasant nor tasty, and any existing milk foam is retained. However, if drunk directly from the glass, it is quite harmonious. In the first tasting, without considering the drinking experience, it lands in second place. However, the positive properties then diminish quite quickly, so it ultimately ends up in the lower third. The KeepCup is therefore also a cup that is more suitable for quick consumption.
To the Keep Cup from the company, Kaffeekommune with logo or Amazon*.
The Ranking
Who would have thought that finding the perfect travel mug would be almost as difficult as finding the perfect espresso? Our test series has shown: not all travel mugs are created equal. Between double-walled stainless steel, robust porcelain, and sustainable coffee grounds, there are not only optical differences but also in terms of thermal insulation, taste, and drinking experience.
Temperature Ranking
During the 2.5 hours tested, the mugs performed differently. From the temperature measurements, we can deduce that thermal mugs with double-walled stainless steel, whether with or without a ceramic inlay, keep coffee warm for a long time. In comparison, to-go cups made of glass, porcelain, or coffee grounds fall short. Either the cups could maintain the temperature for a long time but then failed in terms of taste and mouthfeel. Or they were sensorially okay but cooled down within a very short time.
Regarding temperature, I would like to add the following. Travel mugs where the coffee is already about 10°C below the initial pouring temperature at the beginning have a negative effect on taste and mouthfeel. In general, we can say that the longer the coffee is in the mug and the longer it stays hot, the more its quality decreases. A rapid cooling of the beverage is therefore not inherently bad, but depends on the personal requirements for a mug.
Taste, Mouthfeel and Aftertaste Ranking
All tested mugs changed the coffee over time. Certain mugs stripped the coffee of its character, making it flat, bitter, and unbalanced. Other to-go mugs, in turn, caused an off-taste, giving the beverage a metallic, sometimes stale flavor.
The mouthfeel and aftertaste were also increasingly impaired minute by minute. Some mugs gave the coffee a rough, scratchy texture, while others left a bitter, harsh, long-lasting aftertaste.
Taste, Mouthfeel, Aftertaste and Drinking Experience Ranking
If we now add the drinking experience to taste, mouthfeel, and aftertaste, the ranking changes by a few positions.
For the drinking experience, we paid attention to how it felt to drink from this to-go cup. We tasted all test objects once without the supplied lid, before tasting them again with the lid.
Some of the travel mugs were penalized quite severely for their uncomfortable and impractical lids or the hard edges on the vessel itself. In general, however, we can say that mugs with large openings, whether with or without a well-designed lid, were more pleasant to drink from. In addition, a large opening allows all the foam to be drunk with milk beverages.
Travel Mug, To-Go Cup or Travel Tumbler?
Why are there so many names for a to-go cup? If you look around in everyday life, you actually encounter the practical companion for on the go under very different names. Drinking cup, travel mug, thermal mug, or coffee-to-go cup are just a few of them – but they all mean the same helpful coffee cup for on the go. The multitude of terms shows one thing above all: how popular and versatile this everyday helper has become.
In fact, almost every situation has its own name for the portable coffee cup. In the morning on the way to work, many use a commuter mug or car cup that fits perfectly into the cup holder. In the office, people appreciate hot coffee from an insulated mug or thermal cup that reliably keeps the contents warm. Those who travel a lot might have a robust travel mug or tumbler in their luggage – often simply called a travel mug in English – so they don't miss their coffee at the train station or airport. And in the café around the corner, people talk about a coffee-to-go cup when ordering their drink to take away.
There are also different terms when it comes to material and sustainability. Many today rely on a reusable cup or sustainable cup to avoid single-use cups. Often these reusable cups are made of high-quality stainless steel. Such a stainless steel cup is usually a double-walled vacuum cup that keeps drinks warm (or cold) for hours. Some also simply call it a thermos cup, in reference to the classic thermos flask.
No matter whether it's a thermal mug, travel mug, or coffee cup for on the go – in the end, all that matters is that it does its job well. The crucial thing is that the drink reliably stays warm (or cold), nothing leaks, and the cup is a reliable companion in every situation. After all, it's secondary what name it bears – the main thing is that it fulfills its purpose.
Conclusion
So, no travel mug is perfect. All thermal mugs also share the characteristic that, contrary to some manufacturer claims, they absorb the taste of the beverage. Thus, it is quite likely that the tea the next morning will smell like coffee - and vice versa.
Moreover, most of these mugs are simply too large. Assuming that we pour between 25 ml for espresso and 150 ml for a cappuccino into our coffee beverages to still be able to perceive the coffee itself, smaller sizes would definitely be more sensible.
The test is therefore an ode to conscious indulgence. The true art of coffee drinking lies in taking your time and enjoying coffee in peace. The best travel mug is thus the one that reminds us to simply stop once in a while. And if things have to go fast, this test result will help us find a suitable mug, tailored to the respective need.
Further links and information
Our Filterkaffee-Amigo was used for the tasting.
*Links marked with an asterisk are affiliate links. If you buy something through them, it won't cost you more, but we'll get a small commission, which we'll invest in further test material.
