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REI Co-op Magma 15 & 30 Sleeping Bag Review

The REI Magma 15 and Magma 30 sleeping bags are some of our favorite in terms of quality for money. These bags are ultralight, ultra comfy, and much easier on your wallet than most bags with similar specs. Last season’s Magma bags made our top picks list, and these new bags are also at the very top of our Best Backpacking Sleeping Bags list. The Magma comes in unisex (15 & 30) and the even lighter Magma Trail Quilt (see our full review here).

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Quick Specs

Stock photo of the REI Magma 15 Sleeping Bag with a white background

REI Magma 15 & 30

Price: $429 / $379

Comfort Rating: 21°F / 34°F

Weight: 2 lb 3.6 oz / 1 lb 8.4 oz

Fill Power / Fill Weight: 850 / 23.3 oz., 850 / 12.7 oz.


  • Large variety of size options
  • Generous draft collar blocks chill well
  • No upcharge for long/wide sizes
  • Good price for the warmth
  • No snag zipper
  • Warm
  • Ultralight
  • Small packed size


  • Less spacious in the hood and leg than some
  • We see these as more of 20° & 35° bags
  • No stash pocket



We know what you’re thinking – over $300 for a sleeping bag is pretty expensive. And we agree that it’s a lot of money, however, when you look at bags like the Therm-a-Rest Hyperion or the Western Mountaineering Alpinlite which offer similar specs but have much higher MSRPs, the Magma is actually pretty hard to beat. High-quality down sleeping bags are well worth it in our opinion, but they do tend to be pricey. The Magma is our top pick for all-around sleeping bag value.


The Magma bags are well designed for maintaining heat. The hood has two drawcords for a snug fit around your head and a draft collar around your neck helps keep warm air trapped in the bag. The footbox on the magma bags is actually foot-shaped and features a down filled baffle in the toe box to keep your tootsies toasty. These bags are a true mummy shape with a nice fit that eliminates dead space your body has to heat up before the bag can do its job.


Thanks to the 850-fill-power goose down inside these bags, the magma line is incredibly lightweight. They don’t have a lot of showy features and they have a trim fit making them lighter than most bags in their EN comfort rating category.

Small packed size

Again due to that 850-fill-power goose down, the Magma bags pack down very small. The 15 degree bags pack down to about 5- 7 L. and the 30 degree bags pack down to about 2.5- 3.5 L. We like using Hyperlite Mountain Gear Stuff Sacks for packing small sleeping bags like these, because they’re waterproof and the shape works better than a compression sack inside of a packed pack.

No snag zipper

The zipper on the Magma line is very wide and butterfly shaped. When you zip it, fabric is directed away from the teeth and does not snag easily. The only time we had a small issue with the zipper snagging is down by the footbox where there are two layers of fabric by the zipper track, but it’s easy to gently pull the fabric free. Overall, the zipper is excellent.


We see these as more of 20° & 35° bags

We don’t even really view this as a con, because we’d rarely need a bag warm enough for 15°. But it’s worth mentioning that the ratings listed with the Magma bags are overstated by about five degrees. The Magma 15 is a go-to for trips where we expect the temperature to hover in the 20s, and the Magma 30 is one of our absolute favorite for summer trips when we know nighttime temperatures will stay above freezing.

No stash pocket

Nowadays, some cold weather bags include a zipper pocket for stashing electronics or water filters to prevent them from freezing. The Magma bags don’t have any such pocket. This is certainly not a deal breaker, but it’s a lot more convenient to store your things in a pocket rather than having them roll around loose in the bag with you.

Bottom Line

We love how light and packable these bags are and highly recommend them for those looking to go ultralight on a budget. So which bag should you choose? If most of your trips are during warm summer months and more mild shoulder seasons, the Magma 30 is perfect for you (if you do mostly warm camping, but also take a couple of sub-freezing trips a year, try adding a liner to the Magma 30 to stretch the temperature rating). If you want a bag that will keep you warm down into the 20s for high altitude and sub-freezing trips, the Magma 15 is your bag.

The Magma sleeping bags are our top pick for all-around value and can also be found alongside some other great options on our list of the 10 Best Backpacking Sleeping Bags and Quilts.