We Tested the Best Hot Food Thermoses for a Great Meal Anywhere (2024)

When you're always on the go, it's easy to get into the habit of stopping for a quick-service meal, but relying on fast food can also add up—both calorie- and money-wise. With the right storage containers, taking homemade food along to the office, school, or even on a hiking trail is a cinch.

To help find one that suits your needs, we researched top products suitable for packing up leftovers or make-ahead meals, as well as dishes to add to the kids' lunch boxes. We tested to see how long our best models would keep hot food warm and cold drinks chilled.

Our Top Picks

How We Tested Hot Food Thermoses

Based on extensive online research of available models, we chose a collection of hot food thermoses to purchase and send to our experienced home testers, who filled, sealed, and even intentionally dropped each container to test its effectiveness and durability. We took the temperature of hot food and the measure of the container’s size and shape for packability. We also rated each thermos on design, performance, functionality, and overall value.

We Observed

• How well the thermoses sealed: Before adding any food to a thermos, we filled it to capacity with water to check for leaks. Each thermos was sealed tightly and then tilted on its side onto a kitchen towel. It sat for fiveminutes before we checked for wet spots on the fabric.
• How hot (and cold) food stayed in the thermoses: A thermos was filled to the brim with a variety of hot foods, from soup to stew to mac and cheese. We checked the contents’ initial temperature using an instant read thermometer, sealed the thermos tightly, and checked hourly for five hours to see when and how much the temperature dropped. We tested in the same way with iced beverages.
• How durable the thermoses were—even when dropped: We intentionally let every thermos fall from counter height to the floor while empty. Any body or lid damage was noted, including scratches and dings. We looked beyond the cosmetics for bent edges that prevented a lid from being tightened or an uneven bottom that kept the thermos from sitting flat.
  

We Rated

• Design and functionality: In terms of design, we considered body and lid materials, including whether they are user- and environment-friendly. How smoothly the lid screwed on and off was noted, along with whether the overall size, shape, and mouth opening made a thermos easy or difficult to fill, pack in a lunch bag, and clean. Bonus accessories like a spoon or insulating bag were considered, too.
• Performance: Beyond testing each thermos’s seal and ability to hold heat, we looked at other characteristics that made it perform better or worse than its competitors. When filling a thermos, we noted how easy it was to pour in a soup or stew. We not only checked for leaks but also recorded how badly or how well a thermos held its contents when flipped on its side.
• Value: After testing was complete, we revealed the price of each product to decide whether the thermos was a good value for its price, overpriced, or underpriced based on its performance.
  

What to Look for in a Hot Food Thermos

Design

Food thermoses tend to be shorter and wider than drink thermoses. This is so you're able to pour contents, such as soup, into the flask—and eat out of it as well. Most have a twist-on lid, which helps prevent spills. Some thermoses will have additional seals or interior lids for further spill protection.

Material

Stainless steel is the preferred material for thermoses. It won’t absorb color or scent from hot food that is stored in it for a long time and cleans easily. An inner flask is surrounded by a partial vacuum that won't conduct heat away from the flask, keeping the contents warm. An outer case, usually also steel, allows you to hold the container without condensation or burning your hand. The outer case may also be treated with a coating or surrounded by plastic.

Even inexpensive models tend to be vacuum-seal stainless steel. However, the vacuum-seal method can be used with other materials like glass and plastic. Because they are not as durable as stainless steel, they are not recommended.

Capacity

The size of a thermos largely depends on what you want to use it for. Most thermoses for adults tend to be around 16 ounces, and ones for children are a little smaller. The food will cool down faster if there is excess air in the thermos, so if you want your food to stay hot for several hours, you'll want to use the best size thermos for the amount of food you're putting in it. If you just want the option for a small soup bowl at lunch, you can go with 10 ounces or smaller. If you want to carry a hearty meal in your flask, 16 ounces is likely the better fit.

Price

Thermoses tend to be fairly affordable, and you can typically expect to get a long-lasting one for somewhere between $15 and $30. The more expensive models may boast more fun colors, an extra-strong seal in the lid, or certain accessories, but they all will use the same stainless steel vacuum-sealed design.

Ease of Cleaning

A stainless steel thermos is relatively easy to clean up. Because it won’t absorb scent or color from your food, you can treat it like you would any other dirty dish and wash it with soap and water. Many thermoses are dishwasher safe but not all. This isn’t because of the material but the construction: Dishwashers may mess up the vacuum seal. Interior lids and other accessories, like collapsible forks, may also require additional hand-washing to get rid of built-up grime.

Hiking and Camping Thermos Tips

Hot food thermoses are handy to have around any time, but they can be necessities on hiking and camping adventures. We talked to Kate Bast, nature and forest therapy guide and founder of Shinrin-Yoku Madison, who offered some tips for taking thermoses beyond the classroom or office.

• Hydration: On hot days, Bast recommends hikers bring at least twice as much water as they think they need, even if that means bringing two or more thermoses. She also suggests adding hydration packets to water or filling a thermos with fruits that have high water content, such as watermelon, which can be frozen the night before to maximize coolness. On chilly days, Bast carries one thermos with room-temperature water and another containing a hot or warm beverage.
• Sustenance: "Think about the sustenance you'll need to match your exertion levels and what will be most digestible," Bast says. Her go-to hot beverages include apple or pear slices steeped in cider with maple syrup, white pine tea, and spruce needle tea. For hot food, Bast suggests bone broth, veggie broth, or other soups that you can add proteins to. For something heartier, she suggests a casserole or stew.
• Snow Days: "If you happen to be in a snowy situation after you've consumed your hot thermos items, fill it with clean snow. The residual warmth will help melt it ensuring you have more water at the ready."
• Quantity: "Always have another thermos or two [in the car] of what you brought into nature with you," Bast says. "You'll be glad to have it and be more likely to consume what you need on the trail knowing there's more waiting at the trail's end."

FAQs

Is the brand Thermos trademarked?

Thermos is synonymous with the product it produces—thermoses. But unlike Kleenex and Tupperware, Thermos has not been able to maintain the trademark on the term "thermos." The Thermos company, first started in Germany, was the first to figure out how to take industrial vacuum-sealing techniques and apply them for home use. Today, Thermos makes a wide range of insulated containers, from flasks and mugs to coolers and lunch boxes.

How do I choose what type of thermos to get?

Before purchasing a thermos, narrow down a preferred size and what it will most frequently be used for. This could range from beverages, like coffee and tea, to meals that need to survive a long day and transport to after-school clubs and sports practices. Perhaps durability is the top concern for long outdoor treks. Check customer reviews to read common raves and complaints about each manufacturer’s products.

How does a thermos work?

Using a stainless steel vacuum-sealed design, an inner flask maintains contents at a consistent temperature, since warm or cold air cannot easily penetrate or escape from the flask. The outer material, usually made of hard plastic or steel, allows the thermos to be comfortably held and transported without liquid leaking out.

How long do thermoses keep contents hot or cold?

High-quality thermal flasks can keep food and beverages warm for as long as a full 24 hours. More economical brands will typically retain the original temperature of contents for four to six hours.

Why Trust The Spruce Eats?

Rachel Werner teaches culinary writing through Hugo House and has been selecting food-based businesses for editorial coverage for over six years. Her product and restaurant reviews, food styling, and photography have appeared in a variety of regional and national publications including Fabulous Wisconsin, BRAVA, and Hobby Farms Magazine. For this roundup, she interviewed Kate Bast, nature and forest therapy guide and founder of Shinrin-Yoku Madison.

Abigail Abesamis Demarest is a freelance journalist who specializes in food and drink content. She tested three of the thermoses in this roundup to see how well they kept food warm, if they were leakproof, and how durable they were.