Anyone who enjoys drinking coffee on the go knows the numerous challenges and, consequently, the requirements for the perfect travel mug. These range from leak-proof and spill-proof to temperature-resistant, dishwasher-safe, and easy to handle. Finally, the coffee should retain its true character and taste good even after some time, rather than being masked by metallic notes. In search of the perfect thermal mug, travel mug, or to-go cup, we tested 12 different mugs.
The test criteria
The evaluation of the to-go mugs was divided into taste-related and technical criteria. These have been refined through community feedback and our work with the travel mugs.
We focused on the following criteria:
1. The container's influence on taste
2. The tactile sensation
3. The drinking experience
We tested all 12 to-go mugs over a period of two hours. We tasted the coffee 10 minutes after pouring, then after 30 minutes, one hour, and two hours.
Taste and mouthfeel
We evaluated both the taste—divided into flavor and off-taste—and the tactile sensation, split into mouthfeel and aftertaste. We also recorded how pleasant it was to drink from each individual mug.
Since some of the containers are also intended to be enjoyed without a lid, such as the Loveramics Nomad or the KeepCup, we decided to taste all to-go cups both with and without their lids. As a result, some models performed worse in the 'without lid' category, as they were not designed for that. Conversely, there were also cases where the lid significantly impaired the drinking experience.
Is the temperature constant?
Furthermore, we measured the temperature in the vessels over 2.5 hours. While this did not influence the overall rating, it could affect 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 thermal mugs and measured the temperature immediately. Surprisingly, all test objects lost between 7 and 18 degrees in the first few seconds. It is important to note that none of the mugs were preheated.
Fortunately, the thermal mugs specifically developed for coffee perform best regarding temperature stability over time. The Kinto Travel Tumbler, Carter Fellow Move, and Iris Go are still over 62 degrees hot even after two hours. Our Kaffeemacher mug and the FLSK are also in the upper-middle field.
As expected, the more cup-like products could not maintain the temperature for long. However, one should consider that these are intended for quick consumption and not for longer trips.
The travel mugs tested
Our 12 test mugs can be roughly divided into two groups.
- Leak-proof to-go mugs
- Non-leak-proof to-go mugs
While this classification has no influence on taste or tactile sensation, it helps in selecting a suitable thermal mug according to personal needs. The following table summarizes the most important basic data.
Leak-proof to-go mugs
Emsa Travel Mug Classic (360ml), CHF 23.20 / € 24.52
The Emsa Travel Mug Classic looks like a typical all-purpose stainless steel thermal mug and won't win any design awards. The outside of the mug is wrapped in a rubber coating that keeps the temperature well contained. While the mug is easily opened by pressing a button (Quick-Press) in the center of the lid, it feels a bit unusual to me. However, thanks to the screw cap and the Quick-Press mechanism, it is 100% leak-proof and its shape is also optimally suited for long car journeys. The thermal mug can be taken apart easily and is dishwasher-safe.
To drink from it, you have to tilt the Emsa Travel Mug Classic extremely far. With hot liquid, this triggers a fear of scalding. And some drops may remain in the crevice next to the very high drinking rim.
In terms of both sensory performance and temperature, the thermal mug ranks in the middle. At 85.35°C immediately after pouring, it belongs to the top half of the objects tested. After 2.5 hours, it still holds 53.15°C, placing it in the mid-range. This is actually surprising, as one might have expected better insulation due to the tight seal.
In terms of taste, it is not entirely convincing and lands in the last third. After just 30 minutes, a clearly metallic taste emerges, and the coffee develops a harsh and scratchy aftertaste. To the Emsa mug*.
Kaffeemacher mug (250ml), CHF 29.90
Our Kaffeemacher mug by the brand Aladdin is dishwasher-safe and can be transported in a backpack without worry thanks to the double leak-proof mechanism. The double-walled stainless steel provides good insulation, and the durable powder coating ensures a secure grip. Due to its shape, the thermal mug is versatile and fits well in both the car cup holder and the bottle cage of a bicycle. The mug's drinking opening is small, and the closure does not really give me any joy.
In our comparison, our mug unfortunately did not perform very well. While it does have its fans, in terms of sensory performance, it simply could not keep up with the best. Regarding temperature stability, it plays in the front, performing quite well at 86.63°C immediately after pouring and 56.85°C after 2.5 hours.
However, the mouthfeel and taste leave something to be desired, placing it in the bottom half. Although the coffee in the thermal mug does not noticeably deteriorate over time, it is only in the midfield from the beginning. To the KM mug
Iris Go (200ml), CHF 45.00 / € 45.00
The Iris Go surprises with an unusual look, because unlike all other thermal mugs in the test series, it has no removable lid. The closure hugs the edge of the stainless steel directly when unscrewed. To close it, the lid is simply screwed back on.
Drinking from this soft rubber rim is something some of our test team had to get used to. However, the coffee enjoyment from this large opening is very similar to a cup. Small drawback: when closing, a little coffee or milk sometimes remains on the lid, which can then drip into the bag or dry up.
We performed the leak test without the separately available cover. According to the manufacturer, it is leak-proof even without the cover. However, a few drops leaked out during our test, 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 lid from dirt, which is much more hygienic depending on the intended use of the mug.
With 84.48°C immediately after pouring the coffee, the Iris Go is in the middle of the initial temperatures. Although the temperature is still 62.11°C after 2.5 hours, making it the third-hottest mug in the last measurement, this has less negative influence on the taste and mouthfeel compared to others with such high temperature stability. While the coffee in the Iris Go also becomes flatter and more characterless over time, it exhibits less off-taste.
The Iris Go performed very well across all levels and wins our test series!
On the manufacturer's recommendation, we tested further models regarding leak-proofness. These are generally leak-proof. However, with hot drinks, slight moisture can occur at the top when screwing the lid shut, which can lead to a few droplets. The additionally orderable lid prevents dripping into the bag.
After testing additional models, we moved the mug to the Leak-proof to-go mugs category.
FLSK Coffee Mug (350ml), CHF 39.00 / € 39.00
The bulbous and double-awarded (German Design Award Special 2022, Green Product Award Winner 2022) FLSK coffee mug is comfortable to hold and has an elegant look. The safety closure, the flip lid, seals the drinking opening and can be fixed to the top of the lid so it doesn't get in the way while drinking. A vacuum layer between the stainless steel walls is designed to slow heat loss, while the copper coating further supports this effect.
At 84.67°C immediately after pouring and 54°C after 2.5 hours, the thermal mug remains constantly in the middle range of all test products throughout the temperature measurements.
While the small opening regulates the drinking flow, it also holds back milk foam. Without the lid, the mug offers a pleasant drinking experience, but we were not convinced by the small opening with the lid. Nevertheless, flavor, texture, and aftertaste remain consistently good throughout the entire measurement time, which earns the FLSK coffee mug third place in the end.
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 among many coffee professionals and aesthetes. The test team perceives it positively right away. Its unmistakable Japanese design impresses with minimalism and functionality. An inner shelf holds back ice and herbs (with tea), while the drinking stopper further regulates the liquid flow.
The drinking stopper is an attachment for the stainless steel insulated mug and therefore does not take up space at the bottom, as is the case with the Fellow Carter Move, for example. As a result, the mug can be filled to the top. When unscrewing the lid, the drinking stopper sometimes comes along, which is somewhat cumbersome. Due to its narrow shape, the Kinto Travel Tumbler fits perfectly even in small hands and fits into both bicycle and car cup holders.
With this insulated mug, too, a vacuum between two stainless steel walls prevents heat transfer. Of all the mugs tested, it loses the least temperature and is still at 65.89°C after 2.5 hours. However, that also means it is very hot at the beginning, which can trigger a fear of scalding.
Sensorially, however, the thermal mug (unfortunately) cannot convince and therefore lands in last place. For one thing, we do not find the drinking experience positive. The plastic edge feels unpleasant, and the relation between the diameter of the opening and the depth of the drinking rim causes the nose to bump into the top edge. For another, due to the long heat exposure, the coffee relatively quickly develops a metallic and, towards the end, even a vegetable, herbaceous, 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 has been specially developed for coffee. The ceramic inlay is intended to prevent unpleasant odors, such as a metallic taste. Along with the Kinto Travel Tumbler, the Fellow Carter Move is one of the most popular travel mugs in our community. The snap-in splash guard allows for comfortable “on the go” drinking despite the large opening and protects against spilling. Thanks to the screw cap, the mug is 100% leak-proof.
The Fellow Carter Move is double-walled vacuum-insulated, thus preventing the rapid escape of heat and cold. Concretely, this means that while it loses 10°C immediately 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 period at 65.3°C.
Looking only at the mouthfeel and taste, without considering the drinking experience, the mug reaches rank 4 in the overall ranking. As with all thermal mugs, the quality of the coffee decreases somewhat over time, and a slight bitterness emerges. Nevertheless, the body and acidity remain pleasantly balanced. However, if the drinking experience is included in the evaluation, the Fellow Carter Move slips to eighth place. Although the three of us perceive the metallic edge and the splash guard differently, we find them neither 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 reminds one of a classic disposable to-go cup. The brown color takes some getting used to at first glance and does not look very aesthetic. But this impression is relative, as the mug is made from recycled coffee grounds from Berlin cafés and roasteries, which also explains the coloring. Furthermore, there are no petroleum-based raw materials, meaning the Kaffeeform team is taking a pioneering path. The Weducer Cup is light yet robust and features a disposable-like drinking lid and a leak-proof cap.
Thanks to the double outer shell, the drink remains 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 in the last places of the measurements along with the Loveramics Nomad and the KeepCup. However, this does not have to be negative, as the drink is quite quickly ready to consume. It is therefore recommended to drink the coffee in 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 falls into the last places after just 30 minutes. Although the coffee does not develop a metallic or other off-taste, 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 sliding mechanism that, at least when new, is easy to move and seals well. However, it is not leak-proof and is therefore more suitable for straight or slightly bumpy transport rather than in a backpack. Due to its features, it is a good companion for car trips.
The Yeti Rumbler impresses with its insulation. It loses the least temperature immediately after pouring 94°C hot water and still shows 87.43°C, which represents the lowest loss in the test. Even after 150 minutes, it measures 59.18°C, placing it in the upper third in terms of temperature stability over the entire measurement period.
Drinking through the small opening is rather unfavorable for mixed drinks like cappuccino and flat white, as it holds back all the milk foam. However, drinking without the lid is not recommended, as the edges of the mug are quite rough. Sensorially, the thermal mug performs well at the beginning, but develops a musty, metallic off-taste after about an hour. Furthermore, the coffee loses more and more aromas and becomes flat.
To the Yeti Rumbler at Amazon*.
Asubo Ultimate Mug (355ml), 18.90 CHF / € 17.70
This cup-like to-go cup seems multifunctional and outdoor-ready. I would love to drink soup from it. Yet: The Asobu Ultimate Mug is specially made for coffee and clearly surprises sensorially. Without the lid, it feels as if one is drinking from a normal cup. With the splash-proof sliding 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 all the more surprising since the sliding lid seals the opening but allows a lot of heat to escape. Immediately after pouring, the mug loses 10°C and is in the midfield at 84.19°C. After 2.5 hours, the temperature is still 51.92°C, which reaches rank 8. Places 9-12 only show 42.92°C or less after the same period of time.
The ceramic coating inside is intended to prevent the transfer of foreign odors. The coffee remains surprisingly dense throughout the entire test time and retains a certain structure. Until the last tasting, it has no off-taste and is still sweet and balanced. With this, the Asobu Ultimate Mug surprises us all and lands in second place in our final ranking.
Loveramics Nomad (250ml), CHF 24.80 / € 28.90
A beautiful cup made of double-walled porcelain in the style of Loveramics. But the rubber lid and the tiny little opening are a flop and extremely downgrade the multisensory drinking experience. Because besides the fact that hardly any liquid comes out of the small hole, the coffee assumes the taste of the rubber within milliseconds. Without the lid, however, you have a completely different experience. Drinking directly from the cup is convincing both sensorially and visually all along the line.
The Loveramics Nomad is also not intended for long travel. Despite the double-walled porcelain, it lands in the second-to-last place with 80.01°C immediately after pouring and reaches the third-to-last place with 30.16° C after 2.5 hours.
Sensorially, this was an emotional rollercoaster. Together with the KeepCup, we rated the coffee from the Loveramics Nomad best in terms of taste and mouthfeel immediately after pouring. And without the rubber lid, it is a very pleasant drinking experience, which would place the cup in third place. If you drink with the lid, however, the rubber off-taste immediately masks the coffee taste.
Loveramics Nomad in Switzerland at the 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 were also fireproof, just like the Asobu Ultimate Mug. Then they could serve for coffee in everyday life and be used for the campfire in leisure time. Visually, compared to a Kinto Travel Tumbler or a Fellow Carter Move, it seems much bulkier and less elegant, and looks more like the Asobu Ultimate Mug. We are not quite convinced by how practical this lid is in everyday life. For it is more of a splash guard or a protection against spilling than a real lid, as it cannot be completely sealed.
Thanks to the double-walled vacuum insulation, the coffee stays warmer for longer in this mug as well. Due to the mentioned opening in the lid, the coffee cools down faster and is consequently not leak-proof. In the temperature measurement, the Stanley Legendary Camp Mug lies in the lower area 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 also cannot keep up. Already immediately after pouring, we see comments of metallic taste and slight bitterness. This does not improve over time, and thus the mug lands at rank 10 in the overall ranking.
Stanley Legendary Cup at Amazon* or Stanley.
KeepCup (227ml), CHF 29.00 / € 27.95
A beautiful glass cup with a sophisticated cork band that is available in various versions, colors, and sizes. Thanks to the cork band, the Keep Cup can be held well, although the glass naturally gets very hot. The massive plastic lid unfortunately downgrades the whole thing visually. While the cover protects against spilling, it is not leak-proof.
The glass draws a lot of heat from the coffee from the start, so that it shows only 76.01° C at the first measurement, while the glass itself reaches 60.3 degrees and 46.2°C respectively after 15 minutes. For comparison: thermal mugs like the Kinto Travel Tumbler only show about 25°C outside temperature after 15 minutes.
With the KeepCup, too, drinking through the small plastic opening is neither pleasant nor tasty, and any milk foam present is held back. If, however, one drinks directly from the glass, it is quite consistent. In the first tasting, without taking the drinking experience into account, it therefore lands in second place. However, the positive properties diminish quite quickly, so that it lands in the bottom third in the end. The KeepCup is therefore also a mug more suitable for quick consumption.
To the Keep Cup at the company, the Kaffeekommune with logo, or Amazon*.
The ranking
Who would have thought that the search for the perfect travel mug would be almost as difficult as the search for the perfect espresso? Our test series has shown: a travel mug is not just a travel mug. Between double-walled stainless steel, robust porcelain, and sustainable coffee grounds, there are worlds between them, not just visually, but also in terms of heat insulation, taste, and drinking experience.
Temperature ranking
During the tested 2.5 hours, 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 mugs made of glass, porcelain, or coffee grounds fall behind. Either the mugs were able to hold the temperature for a long time but then failed in terms of taste and mouthfeel. Or they were sensorially ok, but cooled down within a very short time.
Regarding the temperature, I would also like to note the following. Travel mugs where the coffee is already about 10°C below the original pouring temperature at the beginning have a negative impact on taste and mouthfeel. In general, we can say that the longer the coffee is in the mug and the longer it remains hot, the more the quality of the coffee decreases. A rapid cooling of the drink is therefore not per se 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 robbed the coffee of its character and made it seem flat, bitter, and unbalanced. Other to-go mugs, in turn, caused an off-taste and gave the drink a metallic, sometimes musty taste.
The mouthfeel and aftertaste were also increasingly impaired from minute to 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 the taste, mouthfeel, and aftertaste, the ranking changes by a few positions.
For the drinking experience, we paid attention to how it feels to drink from this to-go mug. We tasted all test objects once without the included lid before we tasted them the subsequent times with the lid.
In doing so, some of the travel mugs were penalized quite heavily for their unpleasant and impractical lids or the hard edges on the vessel itself. In general, however, we can state that mugs with large openings, whether with or without a well-designed lid, were more pleasant to drink from. Furthermore, a large opening allows the entire foam to be consumed with milk drinks.
Travel mug, to-go cup, or travel tumbler?
Why are there so many names for a to-go mug? If you look around in everyday life, you actually encounter the practical companion for on the go under quite different designations. Drinking mug, travel mug, thermal mug, or coffee-to-go cup are just a few of them – but they always mean the same helpful coffee mug for on the go. The multitude of terms shows above all one thing: how popular and versatile this everyday helper has become.
In fact, almost every situation has its own name for the portable coffee mug. In the morning on the way to work, many use a commuter mug or car mug that fits perfectly into the cup holder. In the office, people appreciate hot coffee from the insulated mug or thermal cup that reliably keeps the content warm. Those who travel a lot might have a robust travel mug or tumbler in their luggage – in German often simply referred to as a travel mug – so that coffee isn't missing at the train station or airport. And at the café around the corner, people speak of a coffee-to-go cup or a coffee cup to go when ordering their drink to take away.
There are also different terms in terms of material and sustainability. Many today rely on a reusable cup or sustainable cup to avoid disposable cups. Often these reusable cups consist of high-quality stainless steel. Such a stainless steel mug is usually a double-walled vacuum mug that keeps drinks warm (or cold) for hours. Some also simply call it a thermos mug, in reference to the classic thermos flask.
Whether thermal mug, travel mug, or coffee mug for on the go – in the end, only that it does its job well counts. It is crucial that the drink reliably remains warm (or cold), nothing leaks, and the mug is a reliable companion in every situation. Ultimately, it is secondary what name it carries – the main thing is that it fulfills its purpose.
Conclusion
So, no travel mug is perfect. Because all thermal mugs also have in common that, contrary to some manufacturer specifications, they absorb the taste of the drink. Thus, it is quite likely that the tea the next morning smells like coffee - and vice versa.
Furthermore, most of these mugs are simply too large. Based on the fact that we pour between 25 ml for espresso and 150 ml for a cappuccino for our coffee drinks in order to still be able to perceive the coffee itself, smaller sizes would definitely be more sensible.
The test is therefore an ode to conscious enjoyment. The true art of coffee drinking lies in taking time and enjoying the coffee in peace. The best travel mug is therefore the one that reminds us to just stop every now and then. And if it does have to go quickly, then with this test result, we find a suitable mug, tailored to the respective need.
Further links and information
During the tasting, our filter coffee amigo was used.
*The links marked with an asterisk are commission links. If you buy something via them, it doesn't cost you any more, but we get a small commission, which we invest in further test material.
