Thermoses come in all shapes and sizes, but fundamental to any good thermos is the ability to keep your drinks hot or cold for hours on end. No one wants to sit down for lunch after a long morning, open their thermos of much-anticipated soup, only to find it lukewarm. Or, on those hot days, looking forward to some nice ice water after a sweaty workout sesh and finding their thermos drenched with condensation with tepid water inside.
The best thermos is easy to clean, functional, leak-proof, and, most importantly, keeps your drink at that ideal temperature. What makes temperature control possible on a thermos is the vacuum design. Here's how it works—every thermos typically has two walls, between which is a vacuum. Because this vacuum contains no air, it does not conduct heat, which allows the liquid inside to maintain a constant temperature.
If you are looking for a thermos lunchbox to pack food, a thermos coffee cup to keep it warm all day, or simply want a thermos to keep your water cold, you have come to the right place. In this review of the best thermos for 2023, you will find our top picks that meet a variety of needs along with a comprehensive breakdown for each one. So, if you are ready for that cooler weather and want the best thermos to keep tasty fall soups piping hot, read on.
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The Best Thermoses - Our Top Picks
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- Best Overall Thermos: Stanley Unbreakable Thermal Vacuum Bottle
- Best Coffee Thermos: Stanley Classic Travel Mug French Press
- Best Food Thermos: MiiR Food Canister
- Best Travel Thermos: Stanley Classic Trigger Action Travel Mug
- Best Budget Thermos: GSI Outdoors Microlite 570
- Best Design Thermos: Stanley Master Unbreakable 44 oz.
How to Choose a Thermos
Capacity
Capacity is an important consideration because it dictates the volume of the contents. So, how you plan to use the thermos and what you plan to put inside will help you determine the right capacity for your needs. Large thermoses can hold well up to, and sometimes greater than, 40 ounces—a great feature if you plan to pack and bring a lot (think a jug of soup for a family picnic), but not so convenient if you plan to carry it on a shorter walk.
Dimensions
A thermos with a large capacity carries greater dimensions. Depending on your intended use, you will need to carefully consider the dimensions to ensure it is easy to bring along on your next outing.
Lid
A good thermos will not leak. Period. So the lid design should ensure that it is leakproof, will not come off easily, and is easy to clean. An overly complicated lid design will leave you frustrated, as well. The best lids strike a balance between functionality and ease of use.
Best Overall - Stanley Master Unbreakable Thermal Vacuum Bottle
SPECS
- Dimensions: 3.5" x 11.9"
- Weight: 1 lb. 15.4 oz.
- Holds: 25 oz.
- Material: Stainless steel
- Insulation: QuadVac insulation
- Dishwasher safe: Yes
- Microwave safe: No
Incredibly durable and boasting a leak-proof design, the Stanley Master Unbreakable Vacuum Bottle takes the top spot for our best overall thermos. Featuring QuadVac insulation, this thermos is designed to keep hot drinks hot for up to 27 hours and iced drinks cold for up to 4 days. There are some mixed reviews on its ability to keep hot drinks piping hot for the claimed duration, but the majority of users are extremely pleased with the temperature control on this Stanley Master.
Made with BPA-free, one-millimeter thick top-of-the-line stainless steel, the Vacuum Bottle is essentially indestructible. Combined with its watertight, vacuum-insulated steel lid that also serves as a cup, you can toss this bad boy into your backpack without worry of it breaking or leaking. The tradeoff for this rugged design and temperature control is the weight of this thermos, which is slightly heavier than we prefer. A small price to pay for its durability and overall effectiveness.
What We Like
- BPA-free
- Versatile
- Durable
- Great warranty
- Easy to clean
What We Don't Like
- Heavy
- May not fit in some dishwashers (height constraints)
Buy: Stanly Master Unbreakable Thermal Vacuum Bottle
Best Coffee Thermos - Stanley Classic Travel Mug French Press
SPECS
- Dimensions: 3.5"L x 3.9"W x 9.6"H
- Weight: 1.12 lbs.
- Holds: 16 fl. oz.
- Material: Stainless steel
- Insulation: Vacuum-insulated
- Dishwasher safe: Yes
- Microwave safe: No
Looking to keep your cup of joe hot while out and about? Look no further than the Stanley Classic Travel Mug French Press, a uniquely designed coffee thermos with a fully integrated French-press system. This design allows you to make and drink your coffee all from one product, which means less work and clean-up for you.
This vacuum-insulated mug claims to keep your coffee hot for up to four hours. The Stanley Classic Travel Mug French Press features a drink-thru opening on its leakproof lid which effectively prevents any spills. However, several users do report that the lid is overly complicated and slightly bulky, but it is this two-system lid design that makes it leakproof—an especially important feature when sipping on hot coffee.
Holding two full cups of coffee, this travel mug fits into a standard car cup holder.
What We Like
- Fits in car cup holder
- Doubles as a French press
- Leakproof
- BPA-free
- Easy to clean removable plunger
What We Don't Like
- Complicated lid design
- Bulky lid
BUY: Stanley Classic Travel Mug French Press
Best Food Thermos - MiiR Food Canister
SPECS
- Dimensions: 5.2" x 4.1"
- Weight: 14.6 oz.
- Holds: 16 fl. oz.
- Material: Stainless steel
- Insulation: Thermo 3D double-wall vacuum
- Dishwasher safe: Recommended to hand wash
- Microwave safe: No
Whether you are sending your kid to school with some soup on a cold winter day or packing yourself a fruit salad for your next hike, the MiiR Food Canister is guaranteed to keep your next on-the-go meal hot or cold. Constructed with durable stainless steel and finished with a hard shell powder coat, the MiiR has a sleek-looking and compact design. Although the powder coating is attractive, it does prevent you from tossing this canister in the dishwasher. Hand washing this product is recommended.
Inside measure markers allow you to easily identify portion sizes, which is an added perk for those counting macros. A removable nesting bowl can be inserted to keep foods separate, and users appreciate the leak-proof lid that easily twists open. This kid-friendly design promises that your little one won't be left struggling to open their lunch at school. The MiiR is an incredibly versatile food thermos lending itself to a variety of uses—whether it's overnight oats, storing cold ingredients for your next barbecue, or simply keeping some chicken nuggets warm for lunch, the MiiR is a great food thermos.
What We Like
- Easy-to-use lid
- Interior measure markers
- Durable
- Removable nesting bowl
- Versatile
What We Don't Like
- Smooth exterior makes it difficult to grip
- Will scratch if put in dishwasher (hand washing recommended)
Best Travel Thermos - Stanley Classic Trigger Action Travel Mug
SPECS
- Dimensions: 8.9"H x 2.9"W x 2.9"D
- Weight: 5.8 oz.
- Holds: 16 fl. oz.
- Material: Stainless steel
- Insulation: Double wall vacuum
- Dishwasher safe: Yes
- Microwave safe: No
When it comes to a travel mug, convenience and functionality are of top priority. This is why we like the Stanley Classic Trigger Action Travel Mug—a durable, lightweight, and easy-to-use travel thermos. Constructed with double wall vacuum insulation, this travel thermos is designed to trap heat or cold for hours at a time. It neatly fits into a car cup holder and features a trigger-action push-button lid making it easy to sip away while keeping your eyes on the road and one hand on the wheel.
Naturally BPA-free, the Stanley Travel Mug is dishwasher safe and will not rust over time. It is also resistant to coffee or tea stains and available in several colors. Truly, the trigger lid is the most attractive feature. But it is a little hard to clean, which is not a deal breaker but worth noting.
What We Like
- Trigger-action lid
- One-handed use
- Spill-proof lid
- Fits in most car cup holders
- Multiple color options
What We Don't Like
- Lid is hard to clean
- Only holds 16 oz.
BUY: Stanley Classic Trigger-Action Travel Mug
Best Budget Thermos - GSI Outdoors Microlite 570
SPECS
- Dimensions: 8.9"L x 4.3"W x 2.9"D
- Weight: 9.2 oz.
- Holds: 18 fl. oz.
- Material: Stainless steel/polypropylene/silicone
- Insulation: Vacuum-insulated
- Dishwasher safe: No
- Microwave safe: No
If you are looking for a high-quality thermos that won't break the bank, take a look at the GSI Outdoors Microlite 570. This budget thermos is claimed to provide 10 hours of heat and 20 hours of cold retention at a fraction of the cost of its competitors. The MicroLite 570 is made with two-millimeter thick stainless steel, creating a durable but compact thermos.
Weighing just over 9 ounces, this thermos is lightweight and streamlined, making it a great travel companion. The leak-proof, screw-top lid comes with a sealable flip spout and leverage-enhancing lobe for ease of use. Unfortunately, there are some reviews of this lid breaking easily, but with proper care and use, the Microlite 570 should serve you well.
What We Like
- Attached leash
- Lower price
- Lightweight
- Compact
- Flip spout
What We Don't Like
- Reports of lid breaking
- Not dishwasher safe
Best Design Thermos - Stanley Master Unbreakable Thermos Vacuum Bottle 44 oz.
SPECS
- Dimensions: 14.1"L x 6.7"W x 4"D
- Weight: 2 lbs. 14.2 oz.
- Holds: 44 fl. oz.
- Material: Stainless steel
- Insulation: QuadVac double-wall vacuum
- Dishwasher safe: Yes
- Microwave safe: No
Offering the utmost functionality, the Stanley Master Unbreakable Thermos Vacuum Bottle touts the best design in our book. It features an ergonomic steel handle with a molded silicone grip and a vacuum-insulated steel lid cover that doubles as a drinking cup—this thermos' design is impressive. It is constructed with QuadVac insulation designed to keep drinks hot for 48 hours, cold for 35 hours, and iced for up to six days.
As the name implies, this thermos is virtually unbreakable, made with one-millimeter thick, BPA-free stainless steel. Regardless of where or how you plan to use it, you do not need to worry about its durability. There is a steel-lined stopper which some users report does leak, but the overwhelming majority of reviews rave over its leak-proof design
What We Like
- Design
- Functionality
- Durability
- Capacity
What We Don't Like
- Heavy
- Stopper may leak
BUY: Stainley Master Unbreakable Thermal Vacuum Bottle 44 oz.
FAQs About Thermoses
Which thermos stays hot the longest?
Generally speaking, Stanley thermoses will keep contents hot the longest. The combination of their quality material, vacuum insulation, and leak-proof lids create thermoses that will retain heat. Keep in mind that these are generally heavier.
Is a thermos worth it?
A thermos is totally worth it if you want to keep things hot or cold for any period of time. They are durable, well made, and typically easy to keep clean.
How long do liquids stay hot in a thermos?
The best-insulated thermoses can keep liquids hot for up to 24-48 hours.
Is it OK to put cold water in a thermos?
Yes, it is okay to put cold water in a thermos. The insulation from the vacuum walls will keep your water cold for hours.