Updated Jun 29, 2022 7:51 AM
Insulated lunch boxes are 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 ensure it stays fresh—and safe to eat.
There are so many insulated lunch box varieties on the market today, making it hard to know which ones work and for how long. Things like high-density foam padding will keep heat or cold in and keep your food from getting squished, but there may be more to your decision than that alone. We’ve rounded up the best insulated lunch boxes for any situation as well as the primary considerations to make before buying one.
Things to Consider Before Buying an Insulated Lunch Box
An insulated cooler may not seem like something you need to put too much thought into, but like any consumer good, it helps to analyze the purchase more carefully to avoid an impulse buy that doesn’t work for our needs. Many of us use insulated coolers daily to tote lunches to work and even on the weekends when we are out hunting and fishing. With an item that is seemingly so trivial, we use them an awful lot. Before we get to our top picks for the best insulated lunch boxes, we want to take a moment to discuss a few things that may influence your upcoming purchase.
Some of you may think that the intended use is pretty obvious for an insulated lunch box, and you’re not wrong. Generally, we use them to transport food and keep it either hot or cold. Beyond that, the activity you plan to do while taking your lunch box along can influence the materials, size, and durability.
For instance, if the lunch box is primarily used while fishing or on a boat, you are likelier to want something that is hard-sided, seals completely, and is waterproof. Or, if you are bringing it along to a job site every day, you may want something lightweight, easy to carry, and reasonably durable.
All of these factors will play a role in your choice, and identifying the intended use first allows you to narrow down your picks more effectively. Once you’ve done this and know your budget, the rest will follow.
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.
Most insulated lunch boxes utilize synthetic materials. The outer layer needs to be durable, and unless it is a hard, solid single material like plastic or aluminum, it will be made from textiles. The materials will vary and are often a blend of fibers like polyester, nylon, and vinyl. These are chosen due to their overall durability and the low cost of production. However, opting for natural fibers is more environmentally sustainable, but this is relatively uncommon to see with an item like insulated lunch boxes.
The inside of the bag can also be made from a mixture of materials. Most commonly, the interior of an insulated lunch box is made from a water-resistant material like plastic, a foil liner, or aluminum. If the lunch box is one solid material, it will have foam or other insulating materials between the inner and outer walls.
Solid, non-fabric materials are a more durable option, but they are also somewhat clunky and can be heavy. So, knowing how you intend to use the lunch box is important in narrowing down the choice of materials.
Beyond the body of the lunch box, look at the features and what they are made from. If the box utilizes a zipper closure, see if it is made from a plastic material or a more durable metal zipper. If it uses a velcro closure or snaps close with hinges. All of these features have a higher potential for breaking than the body of the cooler itself, so take note of those small things that may be made cheaply but result in the lunch box having a shorter life with you.
Soft-Sided or Hard Case?
A heavy-duty lunch box must 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—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 measurement unit expressing how thick individual fibers are in a material. 1200 denier polyester is an excellent 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.
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 want a water-resistant lining that can be wiped down and repel, rather than absorb, accidental spills. Another option to consider is an antimicrobial lining. The fabric itself isn’t antimicrobial—an antimicrobial coating is applied to synthetic materials, 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.
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.
Insulated lunch boxes with multiple compartments can also enhance the capacity or at least the level of organization. Some lunch boxes will have a hot and cold compartment so you can separate your food and have them be at their respective temperatures.
The size, weight, capacity, and other features can influence insulated lunch box portability. Features like handles or a shoulder strap make them easier to carry, especially if they are large lunch boxes. The type of carrying handles built into the design often reflects the weight.
Thermal insulation and insulated lunch boxes utilizing textiles won’t be very heavy. Ones that are a solid hard-case material will weigh a bit more. What you plan to carry in the box also influences the weight and portability. Consider if you plan to carry a lot of liquid, as that will be much heavier and harder to carry.
Why It Made The Cut: From the trusted Carhartt brand, the Deluxe Lunch Cooler is a functional lunchbox with enough space to pack breakfast, lunch, and a few drinks.
- Materials: 1200-denier polyester with DWR coating
- Dimensions: 10″ x 9″ x 7″
- Capacity: 6 cans
- Multiple compartments
- Easy to carry
- Water resistant materials
- Leakproof liner
- Zipper isn’t the most durable
This classic Carhartt cooler bag has a six-can capacity and several compartments, including a top storage area for things like sandwiches or bananas you want to avoid crushing. With that capacity, it is 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, but it is not adjustable. The primary complaint about this insulated lunch box is that the zippers are not overly durable. They will likely be the first part of the bag to break, so keep them clean and avoid over-packing the bag. Overall, this is an excellent value for the price and is a leakproof, water-resistant lunch box you can take with you to work, picnics, or on the road.
Why It Made The Cut: The YETI Daytrip Lunch Box is a durable, compact, insulated box that is perfect for work and day trips.
- Materials: Hopper’s high density fabric with rubber/foam insulation
- Dimensions: 8.8″ x 5.8″ x 8.8″
- Capacity: 6 cans
- Leakproof liner
- Liner is food safe
- Water-resistant exterior
- Easy to clean
- Can leak from the zipper
- Expensive for the size
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. The interior lining is made with a food-safe material with a firm bottom and is relatively leakproof. The lining should not leak at the seams, but if there is liquid inside the lunch box and it is on its side, it can leak out of the zipper.
Exterior materials are a high density and very durable material with a water-resistant coating, making it an excellent work lunchbox or great for outdoor activities. It is easy to carry and relatively small but still has a 6-can capacity. Overall, this is an excellent option for those looking for a more traditionally sized lunch box with the light weight of soft-sided designs but the durability of single hard material construction.
If the hard-sided design doesn’t suit you, YETI makes a soft-sided day trip lunch bag.
Why It Made The Cut: Thermos is a classic brand for keeping food hot. It has a durable, long-lasting design that can fit well in a large lunch box and is equipped with a spoon.
- Materials: Stainless Steel
- Dimensions: 3.7″ x 3.7″ x 5.5″
- Capacity: 16 oz
- Keeps contents hot for up to 9 hours
- Available in several sizes
- Durable construction
- Not a lunchbox. It’s a food canister.
- Can be difficult to clean
This 24-ounce, vacuum-insulated stainless steel thermos promises to keep contents hot for nine hours and cold for 14 hours. It’s the best Thermos for any outdoor adventure or packing a warm lunch. The main drawback is that it isn’t technically a lunchbox. Luckily, the smaller size does allow it to fit inside larger lunch boxes.
If you want a larger canister, Thermos makes a variety of sizes and has food jars with larger openings making it easier to eat directly from the jar. The 24-ounce canister is large enough for most things but slightly too small to fit entire cans of soup at times. Keep in mind this does come with a spoon that is easy to store and carry with you, but the spoon is small and can make it difficult to eat some food items.
Thermos is a long-standing brand with designs that last decades. Their vacuum-sealed canisters are functional for hot soups, chilis, tea, coffee, and any other hot liquid you’d like to take with you on the go. While they work well for hot foods and drinks, they can keep things cold for much longer than most coolers. Having a Thermos on hand is a great option, especially if you frequently travel or pack a lunch for work or school.
Why It Made The Cut: The Under Armour 12-Can Soft Cooler is double the size of most other lunch boxes and has multiple compartments to keep your food and drinks organized.
- Materials: 420-denier polyester & IsoTec premium foam insulation
- Dimensions: 11.3″ x 11.5″ x 7.5″
- Capacity: 12 cans
- 24-can cooler option also available
- Leakproof liner
- Molle on the front for additional storage
- Condensation forms in hot environments
- Shoulder strap is a bit awkward, especially when the bag is heavy
The Under Armor 12-can soft cooler can double as a large insulated lunch box for long days or more than one eater. This extra-large size is great for lugging around drinks, Tupperware, and utensils for two. If you want an even larger option, they also make a 24-can soft-sided cooler with the same construction and design (except with more space).
Although the 12-can cooler is double the size of many other lunch boxes, it still isn’t quite large enough to fit all bottles as it is designed for cans and food. The interior is durable and leakproof, but avoid letting it tip over, especially if there is loose ice, as it can leak from the zipper. The side pockets and mesh provide additional storage outside the main compartment to pack utensils and other necessary picnic items like hand sanitizer.
This is an excellent option if you are looking for a lunchbox-style cooler that is small enough to lug around but big enough to pack a lunch for two.
Why It Made The Cut: Arctic Zone released a few antimicrobial cooler designs in recent years, and the Titan Deep Freeze is sure to be odor-free and keep your food fresh and cold all day long.
- Materials: 300-denier Polyester Ripstop with TPE Coating
- Dimensions: 15″ x 10″ x 13.5″
- Capacity: 24 cans
- Large carrying capacity
- Easy to carry handles
- Rated to hold up to 2 days of ice
- Reasonably priced for quality
- Not enough external storage for other items
- Plastic clips on strap are not durable
The Arctic Zone Titan Deep Freeze is a portable cooler with a large capacity. Although that is a selling point in and of itself, the biggest draw is the leakproof lining with Microban protection. The antimicrobial lining protects against stains and odors, and they claim it lasts the product’s lifetime. The interior and exterior are easy to wipe clean, and all materials are at least water and stain-resistant.
The 24-can capacity is the largest on our list, and this bag works great for toting drinks to a tailgate party or a full day of fishing out on the lake. While you can unzip the top to pack and unpack items easily, there is also a smaller hatch for quick access to items if needed. While the main compartment is quite roomy, the extra storage is somewhat lacking. The front pocket isn’t very big, and if the cooler is packed to the brim, it is hard to use the side mesh pockets for anything other than a few napkins.
Why It Made The Cut: The Wildkin Insulated Lunch Box is a classic lunch bag design that provides plenty of space and convenience to pack a daily lunch at an affordable price.
- Materials: Ripstop Polyester
- Dimensions: 9.75″ x 7″ x 3.25″
- Capacity: 6 cans
- Easy to clean
- PVC and BPA-free materials
- Extra interior mesh pocket to hold utensils
- Not very big
- Durability is questionable
Affordable, flexible, and easy to wipe clean, Wildkin lunch boxes are known mainly as a kids’ brand. Still, they come in plenty of grown-up-appropriate colors and patterns and work just as well for folks over age 12. The mesh inner pocket is ideal for storing utensils or small items, and the interior pocket provides just enough space to carry an average lunch for the day.
The bag is large enough to fit a classic bento box, a water bottle, ice pack, and utensils. Plus, there’s an additional mesh pocket on the outside.
If this particular style doesn’t work for your needs, there are several other affordable designs and sizes made by Wildkins. Although this is a spot-clean-only lunch bag, the materials make it easy to keep clean. It is easy to see why so many parents choose this brand (other than the excellent price point) because it is made with non-toxic materials and a food-safe lining.
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
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 lunchtime.
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.
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.