Published Jul. 29, 2021

An insulated lunch box is useful in many situations, from a long morning out fishing to spending your day at an outdoor work site without access to a fridge. There’s something equal parts comforting and practical about a hearty homemade meal, so you want to make sure it stays fresh—and safe to eat. High-density foam padding will keep heat or cold in and keeps your food from getting squished. We’ve rounded up the best insulated lunch box for any situation, some of which can hold a six pack in addition to your lunch (or just a whole lot of camping food).

Features to Consider When Shopping for the Best Insulated Lunch Box

To help you narrow down your search, consider how large your insulated lunch box needs to be, whether you prefer a soft-sided or hard construction, and extra features like a shoulder strap, multiple compartments to fit snacks and small valuables, or a shoulder strap.

Soft-Sided or Hard Case?

A heavy duty lunch box needs to be durable enough to get knocked around on a hike or at a job site. Soft-sided styles are easier to pack and lighter weight than hard shell ones—just make sure to pick one in a weather-resistant synthetic material like polyester. Look at the denier count to see how strong the fabric is: A denier is a unit of measurement that expresses how thick individual fibers are in a fabric. 1200 denier polyester is a good measurement to aspire to—most heavy-duty tarps and boat covers fall into this range. If your lunchbox is going to be jostled around a lot, in the back of a truck or on a boat, a hard shell casing or stiffer polyester construction may be better for you than fabric.

Best Soft-Sided Insulated Lunch Box: Carhartt Deluxe Lunch Cooler


Heavy-Duty Fabric

This lunchbox features a weather-resistant 1200 denier polyester outer shell.

The classic Carhartt cooler bag has a six-can capacity. In food terms, that’s big enough for a drink, large sandwich, plus snacks or sides. The insulated main compartment keeps food cold and fresh, and there’s a separate top compartment for smaller bites. A shoulder strap and top handle make carrying easy.

Best Hard-Case Insulated Lunch Box: YETI Daytrip Lunch Box

The molded construction on this YETI lunch box will protect your food even as it rolls around in a backpack or on a truck bed. High density foam padding and magnetic closure are great at retaining temperature.

Do You Want to Keep Food Hot or Cold?

Most insulated lunch boxes can keep hot foods warm for an hour or two. But if you really want your leftover pasta or soup to retain its heat until lunchtime, look for Thermos-style vacuum-insulated stainless steel. This construct is ideal for temperature stability, in addition to being non-corrosive and rust- and dent-resistant. Another benefit of stainless steel is that it stays cool to the touch even if there’s scorchingly hot soup inside.

Best Insulated Lunch Box for Hot Food: Thermos Stainless King 24 Ounce Food Jar


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This 24-ounce, vacuum-insulated stainless steel thermos promises to keep contents hot for seven hours and cold for nine. It’s the best thermos for any outdoor adventure!

How Much Food and Drink do You Need to Carry?

The capacity of most insulated lunch boxes and mini-coolers is described in “cans”—a six-can container or cooler can fit six cola or beer cans, a 12-can cooler can fit two six-packs, etc. While a six-can capacity pack might work well for a small meal and some snacks, if you’re going on an extended day trip, want to bring drinks, or have more than one mouth to feed, look for a 9-can or even 12-can capacity.

Best Large Insulated Lunch Box: Under Armour 12-Can Soft Cooler

Under Armour

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This mini-cooler can double as a large insulated lunch box for long days or more than one eater. The strap and rubber grip make it easy to toss over your shoulder. This extra-large size is great for lugging around drinks, Tupperware, and utensils for two.

How Easy is it to Clean?

Food residue and unpleasant odors can get trapped in the seams, zippers, and corners of an insulated lunch box. So you definitely want a water-resistant lining that can be wiped down and that will repel, rather than absorb, accidental spills. Another option to consider is an antimicrobial lining. The fabric itself isn’t actually antimicrobial—an antimicrobial coating is applied to synthetic fabrics, like polyester or nylon, to keep the fabric from absorbing moisture, odors, bacteria, mildew, and mold.

No matter what type of lunch box you opt for, check your manufacturer’s cleaning instructions to see if your pick is dishwasher safe or even safe to toss in with your laundry. If not, hand wash regularly with water and dish soap. To get rid of stubborn odors, scrub the inside with a one-to-one ratio of baking soda and warm water.

Best Anti-Microbial Lunch Box: Coleman 9-can Soft Cooler


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We like this mid-size Coleman cooler for its nine-can capacity, soft, flexible construction, and the easy-to-carry shoulder straps and handles. Outer pockets let you stash snacks that don’t need to be kept warm or cold. Of course, the antimicrobial lining prevents the growth of harmful bacteria or mold.

Best Cheap Insulated Lunch Box: What You Get for Under $20

While large-capacity and hard shell lunch boxes are often more expensive, you can find an insulated soft-sided style large enough to fit a good meal easily. Remember to look for strong polyester—a denier count of at least 300 is important for durability. A budget lunch box is also great for sending kids off to school or a friend’s house with.

Best Cheap Insulated Lunch Box: Wildkin Insulated Lunch Box Bag


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Cheap, flexible, easy to wipe clean, Wildkin lunch boxes are known mostly as a kids’ brand. But they come in plenty of grown-up-appropriate colors and patterns, too, and work just as well for folks over age 12. The mesh inner pocket is ideal for storing an ice pack or water bottle.


Q: What is the best lunch box for keeping food cold?

That depends on where you’re taking it and how much food you need to keep cool. But, generally, the best lunch box will have plenty of insulation and a secure closure to keep the cold air from dissipating, such as a zipper or a jar-like seal. More “open”-style bags with simple velcro closures are not going to have the cooling power of more secure styles. If you’re taking food and drinks for a group, you may want to think about using an ice chest.

Q: Do insulated bags keep food hot?

It depends on how many ice packs you include and how good the insulation is, but food can typically stay safe and fresh for three or more hours, according to the USDA. Perishable foods can be left out for about two hours at room temperature. But in an insulated bag or box with an ice pack, the USDA says items you pack early in the morning will still be good to eat at lunch time.

Q: Do insulated bags keep food hot?

Insulated bags and lunch boxes can indeed keep food warm. How well they perform will depend on the type of insulation and, especially, the closure. A velcro or zipper closure is going to let a whole lot more heat escape than something that screws closed, such as a thermos food jar. If you truly want to keep your food as warm as you can, look for a thermos-style insulated container rather than a flimsier bag-type container.

Now, It’s Time to Get to Shopping for an Insulated Lunch Box!

Remember, an insulated lunch box should have a tight seal, ideally a screwed on cap or reinforced zippers to retain temperature. If you’re concerned about bacteria or mildew growth, shop for one with an antimicrobial lining. Look for side pockets or inner compartments to separate snacks and beverages, and a study, molded construction if you’re going to move around a lot. Now you’re well on your way to a hot, fresh lunch.