The Best Insulated Lunch Box

Buying Guide

Lunch boxes have come a long way since the metal ones kids took to school decades ago. Today’s lunch boxes are well insulated to allow you to keep food temperatures hot or cold for hours at a time. But these soft-sided lunch boxes also come with some challenges, so it’s important to know what to look for before you shop.

Insulation is the key to temperature control. Although the right insulation can help maintain the cool temperatures your items need in the lunch box after you bring them over from the refrigerator, an ice pack can help. Some lunch boxes also offer separate compartments for cold and hot items to allow you to carry both at the same time.

Storage containers are a great way to pack your favorite items, but it can be tough to find the right size to fit into your lunch box. Some boxes come with containers, making this far easier. If you opt for this, make sure the containers are safe to use in the microwave and wash in the dishwasher. Some lunch boxes come with bento box-style containers, and those are great for keeping portion sizes at a minimum, so look for those if that’s your preference.

For our parenting expert, Kate Desmond, finding an insulated lunch box that’s big enough to fit bento boxes for her kids is a major bonus. This helps eliminate the need for plastic bags, which is another plus.

In addition to compartments for your containers and food items, exterior pockets can come in handy. You’ll have a place to store items like cutlery and condiments or, if you prefer, handy storage for your keys and cellphone. With some lunch boxes, you’ll also get extra pockets on the outside for one or more bottles of water.

“Something to keep in mind if purchasing an insulated lunch box for your kids is ease of opening and closing,” Desmond says. “You want to make sure the box you choose is workable for little fingers. It’s already hard enough for them to put their straw in their juice box and open their yogurt tube, don’t make your kid’s teacher or lunch lady do more work by also having to help them open and close their lunch box.”

When you get home each day, you’ll need to set a little extra time aside to get your lunch box ready for the next use. That means removing all items, wiping the inside clean, and setting it out to dry. You’ll have to wash your containers and make sure they’re ready to go by the next day, if you pack a lunch every workday. Also don’t forget to put your ice packs in the freezer so they’ll be ready for use, even if you aren’t sure how long it will be until the next time you need them.

• If you plan to pack your food in containers, make sure you choose a lunch box that will hold your chosen container size. To make things easier, some bags come with containers that fit perfectly. XM Bag ThinkFit Insulated Lunch Boxes have six food containers and a reusable ice pack. You’ll also get a shaker cup with three storage compartments for mixing meal replacement shakes. Lastly, these boxes include a pill storage container to keep everything in one place. The Zuzuro Lunch Bag Insulated Cooler Lunch Box has three containers, each large enough for a small meal.
• When a lunch box comes with containers, look to make sure you can wash them in the dishwasher, as well as heat up food in them in the microwave. The containers and lids with XM Bag ThinkFit Insulated Lunch Boxes are all dishwasher safe. Although the containers on the Zuzuro Lunch Bag Insulated Cooler Lunch Box are dishwasher and microwave safe, the lids aren’t microwaveable, so you’ll need to take those off first.
• You may need ice packs to keep cold food chilly longer. XM Bag ThinkFit Insulated Lunch Boxes have one reusable ice pack, while the Zuzuro Lunch Bag Insulated Cooler Lunch Box has two ice packs, but you can easily find packs to fit if your chosen lunch box doesn’t come with one.
• Most people want to carry both warm and cold items at the same time. Some lunch boxes meet this challenge by providing separate compartments, each insulated to maintain the temperature of the items inside them. The MIER Adult Lunch Box Insulated Lunch Bag features separate upper and lower compartments that you can use to split up your cold and hot food. The Zuzuro Lunch Bag Insulated Cooler Lunch Box has three separate insulated compartments, along with a fourth area for holding room temperature items like cookies.
• Temperature control is always a challenge, but today’s insulation technology accomplishes this more capably than ever before. XM Bag ThinkFit Insulated Lunch Boxes use double insulation, promising to keep food cold or warm for as long as 10 hours. The MIER Adult Lunch Box Insulated Lunch Bag and MAZFORCE Original Insulated Lunch Bag use thick insulation, while the Zuzuro Lunch Bag Insulated Cooler Lunch Box uses thick PEVA lining.
• One small touch you may not consider when you’re buying a lunch box is an extra storage compartment for items like cutlery and condiments. If you need to tuck a water bottle into a pocket on the outside, look for that, as well. The MIER Adult Lunch Box Insulated Lunch Bag has an extra zippered pocket, while the Zuzuro Lunch Bag Insulated Cooler Lunch Box has both a small pocket for items and two fully-insulated water bottle holders.
• Size can be a challenge with lunch boxes. You want a bag that’s large enough to store all your items, but you also need it to be small enough to be portable. The size you choose will depend on your own personal preferences. The MAZFORCE Original Insulated Lunch Bag is small enough to slide into a backpack or tote bag, but it’s also limited on storage inside, making it more ideal for those who take snacks or small lunches. The MIER Adult Lunch Box Insulated Lunch Bag is larger, but its removable shoulder strap makes it easy to carry as a crossbody bag if you prefer. It still will be too big to squeeze comfortably into your office refrigerator, though.