How to keep your feet warm in a sleeping bag

Cold feet got you down? Learning how to keep your feet warm in a sleeping bag is essential for a comfortable night’s sleep while camping—especially if you’re camping in the shoulder seasons or winter.

Ross and I camped in -35°C (-31°F) up in northern Ontario, Canada in the middle of a snowstorm in February. We never had any issues with cold feet at night, but that’s because we were extremely well prepared for these bone-chilling temperatures.

Why do my feet get cold in a sleeping bag?

There are a few reasons why your feet might get cold in a sleeping bag. The most common reason is that the sleeping bag isn’t designed for cold weather camping. Either that, or your sleep system hasn’t been optimized for maximum warmth.

Another reason why your feet might get cold in a sleeping bag is that you’re a cold sleeper. Some people just naturally sleep colder than others and need to take extra steps to keep their bodies warm at night.

Having cold feet at night isn’t just uncomfortable—it’s actually dangerous. If your feet are cold, chances are the rest of your body is cold too. If your body temperature drops too low, you put yourself at risk for hypothermia. Most people think hypothermia only occurs after being submerged in cold water, but it can actually occur if your body is exposed to temperatures lower than 10°C (50°F) for prolonged periods.

13 tips to keep your feet warm in a sleeping bag

Learning how to keep your feet warm in a sleeping bag starts with the quality of your bag and overall sleep system. Here’s where to start.

1. Get a sleeping bag with the right temperature rating

This is by far the most important tip for keeping your feet warm in a sleeping bag. If your sleeping bag isn’t rated for cold weather camping, your feet are going to be cold—it’s as simple as that.

We explain sleeping bag temperatures here, so we won’t go into too much detail, but one thing to keep in mind is that there are typically two different temperature ratings: the comfort rating and the lower limit rating. The comfort rating is the temperature at which most people will find the sleeping bag is enough to keep them comfortably warm. The lower limit rating is the temperature at which the average person can sleep without feeling cold.

If you just pay attention to the lower limit rating, you’re going to be in for a cold night’s sleep. Why? The lower limit rating is based on how warm the average person can sleep without feeling cold—not how warm they will actually be. Most people feel cold at temperatures well above the lower limit rating.

2. Make sure your sleeping bag has a closed toe box

A closed toe box is simply the section at the bottom of the sleeping bag that covers your feet and doesn’t have a zipper running all the way down. Ideally, you want to zipper to stop at the ankle so that your feet are fully enclosed in the sleeping bag.

If your sleeping bag has a zipper running all the way down around the toe box, there’s a good chance cold air is getting through the zipper into the bottom of the bag and chilling your feet. The design of the bag is to blame.

If you prefer using a quilt rather than a sleeping bag, look for a quilt with closed toe boxes that cinch with a drawstring. This will ensure that your feet are fully enclosed in the quilt and won’t get cold during the night.

3. Regularly inspect your sleeping bag before taking it on a camping trip

Before each camping trip, it’s a good idea to give your sleeping bag a thorough inspection. Check for any rips or tears in the fabric and make sure all the zippers are in working order. If you notice any damage to your sleeping bag, get it repaired or replaced before using it again.

Even small holes and tears can drastically reduce your sleeping bag’s temperature rating. You may be able to sew or patch your sleeping bag yourself, but you’re not sure how, we recommend taking it to a professional.

4. Use a sleeping bag liner

A sleeping bag liner is an extra layer of insulation that goes inside your sleeping bag. It’s especially helpful when you have a summer or three-season sleeping bag and want to add a few extra degrees of warmth to it without upgrading to a whole new bag.

In addition to being a great hack for figuring out how to keep your feet warm in a sleeping bag, adding a liner is an easy and inexpensive way to keep your entire body warm.

5. Fluff out your sleeping bag properly

Sleeping bags are typically filled with down or synthetic insulation. If you have a down sleeping bag, it’s extremely important to fluff it out properly before getting in—especially in the lower area if you suffer from cold feet. This will help the down loft and trap heat more effectively.

The same goes for synthetic sleeping bags. Most synthetic bags have a quilted design that can become matted down over time. If you don’t fluff out your synthetic bag regularly, it won’t insulate as well as it should.

You can also hold up your sleeping back to a lantern, flashlight, or headlamp to see spots within the baffles where the down or synthetic filling looks thin. Try to even out the filling by fluffing up those areas as much as possible.

6. Get your feet off the ground

Some ultralight campers bring shorter sleeping pads or air mattresses to help them save weight and space, but if you’re trying to figure out how to keep your feet warm in a sleeping bag, a short pad isn’t going to do the trick. You need a barrier between your entire body (including your feet) and the cold ground.

If your feet hang off the end of your sleeping pad or air mattress, they’re going to get cold. A good rule of thumb is to get a sleeping pad that’s at least as long as you are tall. That way, your entire body will be on the pad and your feet won’t dip down into the cold ground.

7. Get a good quality air mattress or sleeping pad

The best air mattresses and sleeping pads are the ones that are not only designed to keep you comfortable, but also to keep you warm. Inflatable sleeping pads and mattresses are made with different materials, some of which are better at insulating than others.

If you decide to go with an inflatable air mattress, make sure it has an R-value of at least 3 to 4. The R-value is a measure of how well a material insulates. The higher the R-value, the better the insulation.

If you’d rather go with a sleeping pad, look for one that’s made with closed-cell foam. Closed-cell foam is more dense than other types of foam, so it’s better at trapping heat and keeping you warm.

You may even want to consider using both. We do for our frigid winter camping trips, and this technique works wonders. We actually place our Therm-a-Rest Z Lite pads on top of our Therm-a-Rest NeoAir Xlite air mattresses (4.2 R-value) instead of the other way around, which seems to be much warmer.

Our thought is that the air inside the mattress gets very cold, which transfers through the sleeping pad and then into our bodies. By reversing the order, we put a layer of insulating closed-cell foam between us and the cold air, which helps keep us warmer.

8. Make sure the end of your sleeping bag doesn’t touch the wall of your tent

If you’re sleeping in a standard nylon tent, you may notice in the morning that the end of your sleeping bag is often wet from condensation on the walls of your tent. The condensation develops overnight as your body heat warms up the air inside your tent, and then that moist air touches the cold walls of the tent and condenses.

This moisture can seep through the fabric of your sleeping bag and make it wet. Down doesn’t insulate well when it’s wet, so you’ll want to avoid this if at all possible.

if you’re a tall person or have a very small tent with limited space at the head and foot of your tent, consider bringing a garbage bag and putting it over the foot of your sleeping bag to create a barrier between the bag and the tent wall.

9. Get warm before you get into your sleeping bag

Don’t expect to go to bed with cold feet and be able to warm them up. It’s much harder to warm up your feet once you’re already in your sleeping bag.

Before you get into your sleeping bag, put on a pair of wool socks and give yourself a foot rub. Warm your feet by the campfire from a safe distance if you can. Once they’re warm, put on a pair of wool or down-filled booties (or moccasins or mukluks if you’re winter camping).

Eat a hearty dinner full of warming spices or have a healthy snack with a good helping of fat in it before bed—like some cheese, nuts, or peanut butter. All of these things will help your body generate heat and keep you warm throughout the night.

10. Go to the bathroom before going to bed

Your body actually has to work harder to stay warm when you’re holding urine in your bladder. So, make sure you relieve yourself before you get into your sleeping bag, and do the same if you wake up in the middle of the night and need to go.

If you’re camping in very cold or wet conditions, keep a “pee bottle” in your tent if you’re a guy, or a “pee funnel” if you’re a lady. This will allow you to relieve yourself without having to leave the warmth of your sleeping bag. Just be sure to practice using it at home before you go so you don’t make a mess.

11. Place a hot water bottle inside your sleeping bag

This is a great trick that’s perfect for winter camping. Fill a leak-proof water bottle with boiling water and slip it into the foot of your sleeping bag before you get in. The warmth will radiate through your sleeping bag and help keep your feet toasty all night.

Just be careful not to burn yourself, and make sure the bottle is wrapped in a sock or something to insulate it so you don’t accidentally puncture it in your sleep.

Tip: If you really want to keep your feet warm, you might want to consider investing in a portable propane heater for your tent. Unfortunately, you just can’t sleep with it running.

12. Place your next day’s clothing in the foot area of your sleeping bag

If you have the extra space and want warm clothes to put on the next day, consider placing them at the foot of your sleeping bag. They’ll help insulate your feet—especially if they’re made of insulating material like merino wool or fleece.

13. Sleep with a partner

Sharing body heat is a great way to stay warm without having to generate any extra heat yourself. You can actually get two-person sleeping bags or quilts to accommodate this.

Ross and I have a two-person down quilt we use mostly in the summer months, which has a closed toe box to keep our feet warm. It’s a great option for couples who enjoy being closer to each other at night.

Should you wear socks in a sleeping bag?

Some people hate wearing socks when they sleep, but wearing socks to bed is actually one of the easiest ways to keep your feet warm in a sleeping bag. Your sleeping bag will trap the heat from your body, but if your feet are cold, that heat will just escape through them.

Wearing wool, merino wool, fleece, or synthetic socks (anything except cotton) will help to insulate your feet and keep them warm. They should fit loosely enough that you’re not cutting off circulation, but snug enough that they don’t slide around and bunch up.

Does wearing two pairs of socks keep your feet warmer?

Wearing two pairs of socks doesn’t actually do much to keep your feet warmer. In fact, it can actually make them colder because the extra layer can trap moisture and cause your feet to sweat. But that’t not all—it can also have a compression effect on your feet, which can cut off circulation and make them even colder.

If you’re going to wear socks, stick to one pair. And make sure they’re made of a material that will actually insulate your feet and help keep them warm.

Does putting plastic bags on your feet keep them warm?

This is a trick mainly used by backpackers who want to keep their socks dry from sweat while they hike. It really just prevents moisture from reaching the sock and doesn’t do much for adding warmth.

You’re far better off wearing socks to bed than plastic bags. Not only will the be warmer, but they’ll also be much more comfortable.

How do you keep your feet warm in a sleeping bag?

Are there any other tips we missed? How do you keep your feet warm in a sleeping bag? Share them in the comments below!