Finest Thermos of 2023-2024 | GearJunkie

Whether you’re heading out for a day of hunting, ice fishing, or enjoying the solitude of a winter trail, a warm cup of coffee or a hot lunch can make even the coldest of days feel enjoyable. High-quality insulated food and drink containers can reliably maintain the temperature of their contents for hours on end. The perfect thermos will vary from person to person, but they all have overlapping qualities that make them the ideal piece of outdoor gear.

In our search for the best thermoses on the market, we considered all types: from old-school tacklebox classics to modern drink movers for folks on the go. We narrowed it down to the best-of-the-best according to durability, leakproofness, heat retention, features, and overall capacity. And before we were through with it all, we pit each thermos against the other in our temperature retention test, scrutinizing manufacturers’ claims and finding out for ourselves which mug would keep our coffee piping hot for the longest.

Our experts have toted close to 15 different thermoses over 3 years, taking them out everywhere from early-morning salmon excursions in the Puget Sound to elk hunts in the high country of Colorado, and have settled on these as the best of the best. Scroll through to see all of our recommended thermoses for any autumn morning. We’ve also compiled an in-depth buyer’s guide and FAQ to break down just what makes a good thermos tick. And finally, use our specs chart to go apples to apples on your next thermos.

Editor’s Note: We updated this guide on September 27, 2023 to add our new favorite most durable thermos, the Stanley Master Unbreakable, and averaged our temperature test findings with another year of data.

The Best Thermoses of 2023-2024

Comparison Chart

Looking for something that’ll be used mostly for water? Take a look at our review of the best insulated water bottles.

Temperature Retention Test

In order to better gauge their worth, we subjected each thermos to a rigorous temperature retention test. Typically during a day in late October, as the first winter storms blow in, we assemble all of our thermoses for a showdown. 

Each thermos simultaneously receives a full serving of 212-degree F water, and is then surveyed for temperature at 30 minutes, 1 hour, 4 hours, 8 hours, 12 hours, and 24 hours. While we understand that some folks recommended preheating their thermoses for maximum efficiency, we wanted to replicate the most likely scenario and poured our brew into room-temp thermoses.

Then, seeking an accurate testbed, we chuck our bottles out on our workbench while we get to tinkering. The ambient temperature fluctuates between 48 and 50 degrees F, but all thermoses fare the same treatment. Once completed, we average our findings over previous results.

Thermos Test Results

While a few things didn’t surprise us (we knew there was a reason Grandpa loved his Stanley), there were some notable takeaways we noticed:

• There’s a good connection between lid size and relative heat loss. Thermoses with relatively wide lids (like the Thermos Funtainer and the Hydro Flask Food Jar) lost heat much more quickly than their narrow lid counterparts. Since the lid is the only non-double-wall part on most thermoses, it makes sense that a smaller lid will hold in more heat.
• While we expected the YETI Rambler Mug to lose heat quickly, we were impressed that it was able to stay above 100 F for 4 hours.
• The thermoses can roughly be grouped into three groups: those that were able to maintain at or about 150 degrees after 24 hours (the Stanley Classic, Stanley Master Unbreakable, and Thermos Stainless King), those that could maintain above 100 F (CamelBak MultiBev, Zojirushi SM-TA48, Hydro Flask Standard Bottle, and the Maxsos), and those that fell to room temp (the Thermos Funtainer, Stanley Titanium, Contigo, Takeya, Hydro Flask Food Jar, and the YETI Rambler Mug).

Then, consider if you’ll need the features of a full-fledged thermos, or if you might be well suited with a bottle that’ll keep drinks both hot and cold. Bottles with integrated cups and handles like the Stanley Classic Legendary Bottle are born-and-bred thermoses, while the Hydro Flask Standard Mouth Bottle could easily be used for both.

Note that this is a constantly changing list and that as new thermoses come out we’ll test and add them if we think they made the cut. If you’re looking for a water bottle, check out our lineup of the best insulated water bottles.

Consider how much you usually drink or eat and if it will fit inside the thermos container. Then decide if it’s just for you or if you’re packing lunch or coffee for you and your partner. If you have multiple people sharing a thermos, then a larger capacity is ideal. However, if one cup of coffee is all you need, something closer to the CamelBak MultiBev will suffice.

Insulation

The insulating capabilities of a thermos are what makes them so useful. Most on the market today will utilize vacuum insulation, but some may also use foam insulation. Vacuum insulation tends to work better than foam, making it the standard for quality thermos brands.

In our in-house temperature testing, we found that there’s a reason your grandpa loved his Stanley so much. The Stanley Master Unbreakable Thermal Bottle only fell 50 degrees over a full 24 hours — down to 160 F. That’s still too hot to drink quickly! Close behind were the Thermos Stainless King as well as the Zojirushi Stainless Mug SM-TA48.

Traditional thermos designs, like the Stanley Classic, have two lids: one air-locking lid on the inside and an exterior lid that doubles as a cup. These dual-lid designs are almost always leakproof, especially because both lids have a rubber seal of some kind. Having a secure lid design is necessary when carrying around a thermos of hot water or coffee — not only to prevent spilling in a bag but also for your safety.

Other thermos lids, like that of the Contigo Travel Mug, are more like a travel coffee container lid. They should have a rubber seal and a variation of Contigo’s SnapSeal to cover the drinking spout. These lids will vary from company to company, but be sure to pay special attention to how well the lid seals, especially if you intend to use it backpacking.

If you’re only using the thermos as a food container, look at the opening of the lid or top of the thermos to see how easy it will be to pour. The wider the mouth, the harder it will be to precisely pour. However, a wide mouth can make it easier to eat directly from the thermos.

FAQ