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Warm Weather Synthetic Sleeping Bags

Top Picks

How we choose: The best warm weather synthetic sleeping bags highlighted here were selected based on 171 reviews of 89 products. Our top picks are those that are readily-available in the United States and have received the highest overall ratings from reviewers.

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The North Face Wasatch 40

user rating: 4.5 of 5 (4 reviews)

I bought mine about a year ago to use while bicycle touring/backpacking/canoeing. Light weight, smallish packing size and synthetic fill for moisture issues were my priorities in a new bag for spring summer and fall. Chose North Face because of good luck with the Goliath bag that has lasted ten years and lots of nights out. The Wasatch is put together well, and with a silk liner, socks and a fleece I have lived through some 25 degree nights on mountain tops, though it was not fun. One drawback is the stupid single pull tab that flips to the inside or the outside.

Read more: The North Face Wasatch 40 reviews (4)

Therm-a-Rest Space Cowboy 45F

user rating: 4 of 5 (1 review)

The Space Cowboy is a nicely featured 45˚F/7˚C sleeping bag for those seeking a highly compressible, lightweight synthetic sleeping bag option. This bag is readily stuffed into pack crevices or its supplied stuff sack, taking up less room at lower weight than a number of similarly rated bags (albeit at higher price), while providing mummy bag coziness with a draft tube and draft collar for unseasonably cool nights.

Reasons to Buy

  • Highly compressible
  • Seems true to 45˚F/7˚C rating
  • Nicely featured
  • Includes pad attachment option
  • Designed to partner with other insulating layers

Reasons to Avoid

  • Upper-end price for synthetic summer-weight bag

In the American South where I live, we’ve had the first few flashes of summer-like heat amid cooler spring weather. It’s enough to encourage trip planning for summer treks. Therm-a-Rest’s Space Cowboy synthetic sleeping bag offers a fully featured summer-weight bag that is well suited for such warm-weather trips. I enjoyed testing the Space Cowboy in summer and early fall, but by layering the Space Cowboy with my Therm-a-Rest Corus HD 35˚F/1.7˚ C quilt, I was able to sleep comfortably in the upper 20s˚F/-2.8 to -1.6˚C, too, a layering option Therm-a-Rest had in mind when designing this sleeping bag.

Read more: Therm-a-Rest Space Cowboy 45F review (1)

Wenzel Lodgepole 40° - 50° Sleeping Bag

user rating: 5 of 5 (3 reviews)

The Lodgepole's roomy, oversized fit will allow you to sprawl out while keeping you toasty between 40-50 degrees with its quick-warming brushed liner, cozy fleece collar, and fleece-lined footbox.

Reasons to Buy

  • Oversized
  • Fleece collar
  • Fleece footbox

Reasons to Avoid

  • Boring color

I'm 5'3" and I am a stomach sleeper. I like to have a knee up and in this bag, I can actually put my knee up. This is the biggest plus about this sleeping bag. The fleece collar is great too. I used this in my camper with the ac on 66° so I was able to use it and not sweat to death. The zipper worked great—I hate it when it gets caught over and over again in itself. 

Read more: Wenzel Lodgepole 40° - 50° Sleeping Bag reviews (3)

Deuter DreamLite 500

user rating: 4 of 5 (3 reviews)

I can't believe that someone hasn't already reviewed this sleeping bag! These are my GO-TO warm weather bags, and the ones I use more than any of the others! I have two (2) of these bags, and I highly recommend them to anyone looking for a lightweight, warm weather only sleeping bag!

Reasons to Buy

  • Lightweight
  • Simple, no-frills design, but with some features
  • Inexpensive (when I bought them, anyway)
  • Takes up very little room in your pack
  • Can be used as a liner in other bags, reducing the need to buy an expensive cold weather bag
  • Durable materials throughout (5 1/2 years of proof!)

Reasons to Avoid

  • Zipper will snag if you aren't careful (like ANY bag)
  • Not quite as light as claimed (but who's gonna quibble over 69.8 grams/2.46 oz?)
  • Not usable by tall people—6 ft is about the limit (*UPDATE- they make a Long version now)

This is the color scheme of the bags that I own. Mine don't look quite as tapered as the manufacturer's stock photo. And mine are not quite as "pretty" anymore, either! Lol. BUT, I purchased these bags in May of 2010, and have used them (with a silk or silk blend liner) on EVERY warm weather trip since then. These bags have gotten more use than all of my other bags combined! So I can confidently say that they are well built and made of durable materials. The standard "legal" tag. The Facts (Yawn): Construction, top and bottom: Mummy sleeping bag, 1 layer Thermo construction Outer/Cover: 100% Nylon [210T Nylon Ripstop] Lining: 100% Nylon [237T Nylon Tactel Taffeta (breathable)] Filling: 100% Polyester [Polydown Soft Polyester] Fill weight: ~160...

Read more: Deuter DreamLite 500 reviews (3)

Ferrino H.L. Micro

user rating: 5 of 5 (5 reviews)

This has to be the lightest, smallest sleeping bag that you can buy and use for serious hiking/camping/mountaineering. It stuffs down to the size of a football, weighs less than 2 lbs. and dries in a flash. Obviously, there is a compromise: this bag simply will not keep you warm enough to sleep below about 32 f., and anywhere around freezing you really should use it with some form of bivy sack or other supplemental bag. However, it does open the door for some really minimalist hiking possibilities (e.g., multi-day trips with a "day pack"). Well designed and constructed, although its lightweight materials might lessen durability.

Read more: Ferrino H.L. Micro reviews (5)

Sierra Designs Backcountry Bed Duo SYN 1.5-Season

user rating: 5 of 5 (1 review)

Someone who sleeps with a partner will find this bag has such great design features that they will know the person who designed it loved and hated doing this many times in the past. tThey distilled all these experiences in one great couples bag!

Reasons to Buy

  • Great design and quality
  • Good mix of access options
  • Built-in and adjustable mattress pockets
  • Ability to cool your feet
  • Buttons make repair easy if needed

Reasons to Avoid

  • Use of buttons was a surprise and awkward
  • Could use a little more width in hip area

I am 5'8" and weigh 240 lbs and my partner is 5'5 "and weighs 130 lbs. Most of my weight is in the belly, cursed that I am! Considering my proportions, this bag was just a little snug at the mid-section when laying flat next to my partner...not too snug and plenty of room sleeping on our sides as normal. Main Point: I have used zip together bags in the past by Slumberjack. These are very comfortable, but you still have legs parted due to the two bags' foot sections where there is no zipper. Also in spite of the fact there is a large flap to cover the zipper it seems it usually goes the other way thus exposing a cold zipper...and this zipper ends up right on top of you and underneath your partner dead center.

Read more: Sierra Designs Backcountry Bed Duo SYN 1.5-Season review (1)

Mountain Hardwear Lamina Z Spark 34

user rating: 5 of 5 (1 review)

This is a great all-round three-season sleeping bag. It's comfort rated down to 34°f, and compresses really well. The outer shell is waterproof, and even though it is a mummy style sleeping bag there is plenty of room inside to move around and get comfortable.

Reasons to Buy

  • Compresses very well
  • Warm, comfortable 3-season sleeping bag
  • Large foot box
  • Lots of room for a mummy style bag
  • Waterproof outer shell

The Mountain Hardwear Lamina Z Spark sleeping bag is a 3-season sleeping bag that is comfort rated down to a temperature of 34°f/1°c.  I have used this on several trips with temperatures dropping as low as 3°c, and felt no chills at all while using this sleeping bag.   This sleeping bag weighs in at a reasonable 1 kg, that's only 2.2 lbs., and it compresses very well so it does not take up too much room. For a mummy style bag, there is plenty of room inside with lots of shoulder room and a very large foot box.   Please check out my review video to see all the features of this excellent sleeping bag.  Thanks.       -Wayne  

Read more: Mountain Hardwear Lamina Z Spark 34 review (1)

Mountain Hardwear Lamina 35°

user rating: 4.5 of 5 (3 reviews)

I love this bag. I also have another colder weather bag but just keep using this one.  If really colder and below the bag rating I use a liner. I never used to use mummy bags but this one works out. Not quite as restricted as some other mummy bags which works for me and still keeps me warm. It is a synthetic bag so loft is not quite as good as a down of equal thermal value but I love it.  A little more reliable in wetter or damper conditions and I pull it out as soon as the tent is set and the lofts comes back soon there after.

Read more: Mountain Hardwear Lamina 35° reviews (3)

The Backside Backsider X-Fibre 35

user rating: 4.5 of 5 (3 reviews)

Excellent bag! This bag's fill (The Backside's X-fibre) is very close to goose down in terms of weight and performance. The bag stuffs to the size of a football. Since I am allergic to down the X-fibre insulation is just perfect for me. I purchased this bag to take the chill out of Wisconsin's cool nights which are in the 40+ degree range. The Backsider bag is just the ticket for a comfortable nights sleep! This bag is very soft, the inside liner that is. It is polyester with an diamond ripstop outer shell.

Read more: The Backside Backsider X-Fibre 35 reviews (3)

More Reviews of Warm Weather Synthetic Sleeping Bags

Trailspace reviewers have shared 171 reviews of 89 different warm weather synthetic sleeping bags.

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Other Types of Warm Weather Sleeping Bags

Find more warm weather sleeping bags reviewed in these related categories:

Warm Weather Down Sleeping Bags

all Warm Weather Sleeping Bags (above 35°F)

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