Best Sleeping Bags for Hot Weather of 2025
A good night’s sleep is essential for a good camping and backpacking experience. Choosing a sleeping bag for cold is easy because you look for the warmest, bulkiest one you can find for the temperature at your camping site. But choosing a sleeping bag for warm weather is different. You have to find a sleeping bag that keeps you warm through the night but doesn’t overheat as well. Summer bags are single-season and lightweight. So, if you are looking for a sleeping bag for your hot weather adventures, then this guide can help.
Below is the list of best sleeping bags with just enough insulation that will keep you warm on summer nights without overheating.
1. Marmot Voyager
Rated to: 45/55°F
Weight: 1 lb. 8 oz.
Fill: SpiraFil
Shell material: Polyester
Marmot Voyager is a warm weather sleeping bag that is available in 45 and 55°F versions. The bag features SpiraFil high-loft insulation that increases warmth and adds to its durability. There’s a two-way full-length YKK zipper, which is snag-free and easy to use. The quality of the bag is good and feels premium. Personally, I like this fabric because it feels cozy when compared to other slippery sleeping bags. The pack size is reasonably small and takes up hardly any space in your backpack. The bag weighs around 1 pound and 8 ounces, which is very lightweight if you consider the size of the bag.
Marmot Voyager may not be warm enough for some colder nights. However, if you live in an area such as Southern California where the climate doesn’t get too extreme, you can use this bag from spring to fall nights and it will keep you warm. Also, the 45°F is best suited for the 50s because I got a little cold sleeping in it at around 45 degrees outside in a hammock when I was camping in West Virginia. However, you use a sleeping bag liner to increase the warmth a little bit say up to 5°F. You can also wear clothes in layers to keep yourself warm if you need to.
What I like: Lightweight, packs small, and good price
What I don’t like: Restrict around legs and shoulders
View Voyager 55 at Amazon View Voyager 45 at Amazon
2. Sea to Summit Spark
Rated to: 45°F
Weight: 12.8 oz.
Fill: 850+ fill-power goose down
Shell material: 10-denier nylon
The Sea to Summit Spark 45F is an excellent choice for ultralight adventures in warm weather. Weighing only 12.8 ounces, it packs down to the size of a 1-liter Nalgene bottle. The 850+ fill-power RDS-certified goose down provides impressive warmth for its weight. A non-PFAS Ultra-Dry Down treatment enhances thermal performance by repelling moisture. The 10-denier shell is lightweight yet durable, offering wind and condensation resistance. The water-resistant hood and footbox add protection in damp conditions. Inside, a breathable 10-denier nylon liner ensures comfort without overheating. The mummy shape, anatomic footbox, and technical hood help retain warmth without feeling too restrictive. A half-length YKK #5 zipper with a zipper plow allows for easy entry and prevents snagging. The sewn-through baffle construction keeps the weight minimal but sacrifices some heat retention.
For warm summer nights and minimalist trips, the Spark delivers an excellent balance of weight, warmth, and packability. It’s best suited for low elevations and mild temperatures. It performs well for cowboy camping, but the thin materials are not very abrasion-resistant. Some may find the fit snug, especially taller users. Our 5’8″ tester preferred the long version over the regular. Despite these minor drawbacks, the Spark disappears into your pack or pannier better than most sleeping bags. If you need an ultralight, ultra-compressible option, this is a solid choice. Plus, it comes with the Sea to Summit Guarantee for peace of mind.
What I like: Extremely light and highly packable; wet-weather assurance of hydrophobic down.
What I don’t like: Only warm enough for mid-summer use.
See the Sea to Summit Spark See the Women’s Spark
3. Therm-a-Rest Vesper
Rated to: 32°F
Weight: 15 oz.
Fill: 900 fill Nikwax hydrophobic down
Shell material: 10D ripstop nylon
The Therm-a-Rest Vesper 32 is a great choice for ultralight backpackers who prioritize weight savings. At just 15 ounces, it’s one of the lightest sleeping bags available. Most of its weight comes from the hydrophobic down fill, which makes up 9 of those ounces. This means there isn’t much excess fabric, keeping it compact and easy to pack. It also compresses down really small, making it ideal for those who like to travel light. The 10D nylon fabric feels soft and doesn’t cling to fleece clothing, adding to the comfort. The Synergylink Connector strap and the collar snap are well-designed, staying low-profile and unobtrusive. We also liked the differential fill, which helps keep warmth where it’s needed. However, the foot box could be a little wider for extra comfort. Still, if weight is your main concern, the Vesper 32 is a strong contender.
While the Vesper 32 excels in weight and packability, it has some downsides. The warmth rating is a bit misleading, which could be an issue in cooler temperatures. The bag’s “limit” rating is advertised at 32°F, but the true “comfort” rating is closer to 41°F. This means it’s best for summer trips rather than colder conditions. A few small design tweaks could have improved its warmth and versatility. That said, for a midrange price, it offers a decent trade-off between weight and performance. Other options might provide better overall value, but few match the Vesper’s ultralight appeal. If your priority is going as light as possible, it’s worth considering. However, if you need more warmth, you might want to look elsewhere.
What I like: Water-resistant down, lightweight, nice fabric
What I don’t like: Snap sometimes comes undone
4. Western Mountaineering HighLite
Rated to: 35°F
Weight: 15 oz.
Fill: 850+ fill down
Shell material: ExtremeLite
The Western Mountaineering HighLite is an incredibly lightweight and compact sleeping bag. It weighs just 15 ounces, making it one of the lightest options available. Its small packed size allows for easy storage in a 5.5-liter stuff sack. The HighLite features 850 fill power down insulation, sewn into horizontal baffles. This helps keep the weight low but reduces warmth compared to other bags. It has a low-volume cut, so there is less space to heat up. However, we found it less comfortable at its recommended 35°F rating. It works best for summer camping or mild conditions. The included hood helps retain warmth, but the bag lacks the full insulation needed for colder nights. The stuff sack adds 1.5 ounces to the overall weight, but the total remains impressively low.
Despite its premium materials, the HighLite was one of the lower-performing bags we tested. The sewn-through construction limits warmth by allowing heat to escape at the stitching lines. While it lofts well after unpacking, it doesn’t trap heat as effectively as competitors. We really wanted to love this bag, but it fell short in colder conditions. That said, it is still an excellent choice for ultra-light backpackers. If you prioritize weight savings over warmth, this bag could be a great fit. However, for true three-season use, other options may be better.
What I like: Ultralight, packs down small, and finely crafted
What I don’t like: The hood and collar don’t seal well
See the Western Mountaineering HighLite
5. REI Co-op Magma
Rated to: 30°F
Weight: 1 lb. 8.4 oz.
Fill: 850-fill goose down
Shell material: Pertex® 15D ripstop nylon
The REI Co-op Magma 30 is another entry on this list from REI but this one is a high-end option as opposed to the Helio Sack 50. But compared to the bags of similar performance and features, the Magma still costs less making it a great value sleeping bag. The Magma features 12.7 oz of 850 power goose down fill. This fill is among the best quality you can get and provides excellent warmth despite the low weight. The total weight of the Magma is 1.5 pounds, which is surprisingly light for the warmth it provides.
The bag also has a mummy shape which makes it warmer by retaining body heat. But the bag has a 63-inch wide shoulder girth that feels roomy. People with wide bodies would also feel comfortable in this bag. It has a durable nylon shell that will last long. Being a down fill bag, the Magma packs down extremely tight. The minimum size of this bag is only 6.7 liters and to achieve that compression, you would need a third-party compression sack. The stuff sack that comes with the Magma has simple drawstrings. The Magma is not a cheap bag. But compared to the competition, you will start seeing the value of this bag. Plus, being an REI bag, you would find this bag mostly on sale.
What I like: Quality down, cozy fabric, lightweight, and packable
What I don’t like: The temperature rating is not accurate, can feel chilly even in the mid-30s
6. The North Face One Bag
Rated to: 5/20/40°F
Weight: 3 lbs. 12 oz.
Fill: 800-fill goose down
Shell material: 20-denier nylon
The North Face One Bag is a unique entry on this list. It is one of the most popular options on the market due to its versatility. But the system integrated to make it versatile also makes it heavy. Needless to say, this isn’t something for the lightweight backpacker. The One Bag is a 3-in-1 bag. The name is confusing because it is not one bag. Instead, it has one lower half and two interchangeable uppers having temperature ratings of 5, 20, and 40°F. Perhaps, The North Face named it the One Bag because it is the only one of its kind on the market. Its 3-part design makes it unique and extremely versatile. The lower part and the two uppers can be used together to achieve a temperature rating of 5oF for winter camping. But the bag becomes an abomination to pack with all three parts.
The bag has a synthetic fill. But even for a synthetic fill, the uppers are heavy. It’s not because of the low quality of material but the addition of a 3-in-1 system with all the zippers makes the uppers heavy. However, this is an extremely thought-out bag with every feature being functional. There is generous space inside making the bag comfortable to use. Having a synthetic fill keeps the cost of this bag low. Down fill would have made the bag lighter but it would have driven the cost up. The versatility of this bag at a reasonable price makes it one of the good value bags that you can get.
What I like: Extremely versatile, good value for money, very spacious, excellent hood design
What I don’t like: Heavy and large pack size
7. Marmot Always Summer
Rated to: 40°F
Weight: 1 lb. 11 oz.
Fill: 650-fill duck down
Shell material: 20D nylon
This bag is made for summer backpacking adventures because it compresses down small but packs a lot of warmth for its size and weight. This is a great option for a backpacker who also does a lot of car camping and doesn’t want or need a super-slim mummy cut but can afford a little more weight for room to sprawl. The hood is nice and big but can be cinched down on chilly nights. There’s a small zipper on the other side of the bag so you can vent it out and fold it down like a blanket. There’s plenty of room in the shoulders and the hips and then it tapers down through the legs for warmth but opens up again at the foot box so your feet have room to move.
The 650 fill power down makes it easy on the wallet while still delivering high quality. The down plumes are treated with Marmot’s down defender, which is a treatment to make the down resists moisture. It acts as a synthetic material in damp conditions to keep you snuggly warm out there. Marmot also uses EN ratings, which stands for European Norm and it’s the most reliable temperature rating in the outdoor industry. When a bag is EN tested, you know what to expect when you take it into the backcountry because they give a temperature and a comfort rating.
To maximize warmth, this bag has an insulated draft tube behind the zipper and it has ground-level side seams so more material is above you to trap in your body heat. It may seem like a small feature but it makes a big difference especially if you’ve ever slept a chilly night in a drafty bag. If you do get chilly, snug the hood zip up all the way but if it’s warmer, vent the bag with the two-way zipper and with the extra little zip on the side.
What I like: Packs down to a small size and big enough to roll around a sleeping pad.
What I don’t like: Narrow fit for folks who like to move around during the night.
8. Nemo Forte Endless Promise
Rated to: 35°F
Weight: 2 lbs. 2 oz.
Fill: PrimaLoft RISE synthetic
Shell material: 30D ripstop polyester
The Nemo Forte 35 is another popular sleeping bag for warm weather camping. The Forte has a decent price with good features making it a good value option. The Forte excels in comfort and has a durable construction that will last a long time. The shape of the Forte is a spoon shape or an hourglass shape. The shape is roomy and allows room. It is looser at every point – shoulders, hip, feet – than a regular mummy. The shape is most suitable for those who aren’t sure about the regular mummy shape and find it claustrophobic or tight for themselves.
The weight of the Forte is around 2 pounds with the regular version which is bulky. However, the women’s long version has been reported to be more comfortable than the unisex bags. The Forte also features Thermogrills for ventilation that extends the temperature range of the bag. Inside is a 20-denier nylon taffeta lining that is softer than others while the 30-denier ripstop polyester shell makes it very durable. You also get a pillow jacket that you can stuff with a jacket or clothes or a pillow for support. Nemo also gives a lifetime warranty with the Forte.
What I like: Good knee and elbow room for side sleepers, can be your go-to 3-season option
What I don’t like: Can be tight for bigger folks, and large pack size
See the Nemo Forte See the Women’s Forte
9. Kelty Tuck
Rated to: 40°F
Weight: 3 lbs. 3 oz.
Fill: Synthetic
Shell material: 75D polyester taffeta
The unique features of Kelty Tuck are designed especially for warm weather camping and at an affordable price. If you are looking for a good budget bag, then Tuck 40 is something to consider. The feature of the Tuck is its zipper that extends normally throughout the length of the bag but cuts near the foot. This cut allows the user to sleep with the feet hanging out. The zipper also allows the bag to open completely like a quilt.
The Tuck weighs a hefty 3 lbs. The weird part is that the weight is the same for the 20°F version and the 40°F version. How did they manage to mess up like that? Overall, the heavyweight made sense because of a creative zipper but the 40°F version should still have been lighter than the 20°F version.
However, the sleeping bag provides good comfort. The shell is made of 75-denier polyester that is extremely durable while inside, you get polyester/taffeta lining. You also get an internal headphone pocket that has enough room to fit a phone. It is good for small things. However, the warmth is not so good. You would need layering with the slightest dip in the temperature. It is great for short trips. At a price this low and the performance that it provides, this isn’t a bad choice by any means.
However, the sleeping bag provides good comfort. The shell is made of 75-denier polyester that is extremely durable while inside, you get polyester/taffeta lining. You also get an internal headphone pocket that has enough room to fit a phone. It is good for small things. However, the warmth is not so good. You would need layering with the slightest dip in the temperature. It is great for short trips. At a price this low and the performance that it provides, this isn’t a bad choice by any means.
What I like: Affordable and durable materials
What I don’t like: Heavy
10. Marmot NanoWave
Rated to: 45°F
Weight: 1 lb. 13 oz.
Fill: Spirafil synthetic
Shell material: Polyester
The Marmot NanoWave 45 is a high-quality sleeping bag at a great price. The long version of this sleeping bag weighs 2 lbs. and the regular version weighs 1 lb. 13 oz. The weight is as much as expected from a synthetic bag like this would. The NanoWave features a mummy shape with a blanket construction that eliminates cold spots. The bag also features the innovative Spiralfil consisting of large, hollow synthetic spiral fibers with small polyester fibers. The resulting fill packs down compact. The compressibility is impressive for a synthetic bag.
The NanoWave is focused on comfort. The chest area and the foot box are provided with brushed lining that provides warmth and adds to the comfort of the sleeping bag. The shell has a DWR coating that is effective in protecting it from moisture. The NanoWave 45 is advertised as a three-season sleeping bag but it is recommended to only use it for hot & humid weather. It lacks a full draft collar and doesn’t provide adequate warmth in cold weather. The stuff sack that comes with the bag is too small so you would have to look for a compression bag. But it’s a solid performer at a lower price making it one of the best budget options as well.
What I like: Great value, packs down small, quality materials, nice to touch, and easy to zip
What I don’t like: Awkward fit, the hood bunches behind the head during the night
Best Hot Weather Bags: Comparison Table
| BAG | RATED TO | WEIGHT | FILL | SHELL MATERIAL |
|---|---|---|---|---|
| Marmot Voyager | 45/55°F | 1 lb. 8 oz. | SpiraFil | Polyester |
| Sea to Summit Spark | 45°F | 12.8 oz. | 850+ fill-power down | 10-denier nylon |
| Therm-a-Rest Vesper | 32°F | 15 oz. | 900 fill Nikwax down | 10D ripstop nylon |
| WM HighLite | 35°F | 15 oz. | 850+ fill down | ExtremeLite |
| REI Co-op Magma | 30°F | 1 lb. 8.4 oz. | 850-fill goose down | 15D ripstop nylon |
| The North Face One Bag | 5/20/40°F | 3 lbs. 12 oz. | 800-fill goose down | 20-denier nylon |
| Marmot Always Summer | 40°F | 1 lb. 11 oz. | 650-fill duck down | 20D nylon |
| Nemo Forte | 35°F | 2 lbs. 2 oz. | PrimaLoft synthetic | 30D ripstop polyester |
| Kelty Tuck | 40°F | 3 lbs. 3 oz. | Synthetic | 75D polyester taffeta |
| Marmot NanoWave | 45°F | 1 lb. 13 oz. | Spirafil synthetic | Polyester |
How to Choose Sleeping Bags for Hot Conditions?
Summer camping is a fun activity and you don’t have to pack a lot as you do in winter. Heavy packing in hot weather can also get tiring quickly. It is best to pack light in the summer. Summer sleeping bags are single-season sleeping bags that are extremely lightweight in most cases due to less insulation. There are several choices on the market based on insulation, shape, and comfort. With the increase in options, choosing a bag has become a bit confusing. Choosing bags for the summer is different than a 3-season sleeping bag. But this guide is here to help you get through the sleeping bag choosing process.
Campground Knowledge
Knowing your campsite can give you an idea of how the bag will be used. This knowledge, in turn, also helps you choose your sleeping bag. You have to have a basic idea of the weather conditions you would be facing at the campsite.
Based on the knowledge that you have about the camping site, you can plan small things like sleeping outside or inside the camp, shelter planning, etc. Keep in mind the altitude when planning your camping trip. The weather is warm at a lower altitude. But things change at high altitudes. The weather becomes cold and the wind speed increases.
Temperature Rating
All sleeping bags for camping come with a temperature rating that is included in their description. Summer sleeping bags are rated 35°F and above. It is recommended that you buy a bag that is rated lower than the lowest temperature you are going to face on the camping site.
If the temperature rises, you can unzip the bag for some ventilation. But if the temperature drops, it becomes difficult to warm up a cold sleeping bag. That can be detrimental to a good night’s sleep.
Insulation
Sleeping bags come with two types of insulation; down fill and synthetic fill. Both have their advantages and disadvantages.
- Synthetic Fill: uses synthetic fibers – polyester, nylon, etc – for warmth. Synthetic fill is found in budget sleeping bags because it is easy and affordable to manufacture. But synthetic fill is heavier, and bulkier than down fill, and doesn’t last long. The only benefit of synthetic fill over down fill in terms of performance is that synthetic fill retains its insulation after getting wet.
- Down Fill: is made of goose feathers. It provides more warmth, is lightweight, and it is easy to compress. Being lightweight makes down-fill sleeping bags attractive for lightweight backpackers. Down fill also has a long life and can last a lifetime if taken care of. The only downside to down fill is that when it gets wet, it loses insulation, becomes heavy, and is hard to dry. Manufacturers use many water-resistant treatments on down fill to protect it from getting wet. Down fill is expensive and time taking to manufacture, and so, it is found in high-end sleeping bags.
Shapes
Sleeping bags come in different shapes for different types of people. Most bags have a rectangular shape because campers like more space. If you want to find a suitable shape for yourself, the only to find out is to use the bag.
The different shapes of sleeping bags are as follows:
- Rectangular – This is the most common shape for a sleeping bag. Rectangular sleeping bags have a lot of room for you to roll over and stretch your arms and legs. These bags can be unzipped completely to be used as comforters. They are most suited for summer.
- Semi-rectangular – This shape is also known as a barrel or modified mummy. This shape is a compromise between room and heat. Semi-rectangular bags are for those who find mummy-shaped bags too constricting.
- Mummy – This shape has a snug fit; you roll over with the bag rather than inside it. Mummy-shaped sleeping bags are the lightest and the warmest. It is suitable for cold temperatures. But this shape is not for people with claustrophobia.
Liners
Sleeping bag liners are layers that can be added to the inside of the sleeping bag a layer to make the sleeping bag warmer. Liners add versatility to the sleeping bag. They are great for campsites with varying temperatures or crowded campsites with varying altitudes. Liners come in all shapes of bags.
