Gear Review: Big Agnes Torchlight UL 20-Degree Sleeping Bag

In this strange, virus-infected spring, I find myself swooning to a new love, the Big Agnes Torchlight UL 20º, sent to The Trek for review. Though not able to road-test it as I might have in the absence of a pandemic, I’ve slept with it every night since receiving it in late April, in conditions ranging from my bed at home to cowboy camping on the high plains of New Mexico and in a tent on the Colorado Trail. She’s everything I’ve ever wanted, and, with a clever system to provide extra room, a little more.

A confession: I’ve fallen in love with all three sleeping bags I’ve owned. Squishy, silky, warm, and soft; what’s not to love? One summer as a boy, I slept outside almost every night in Boulder, Colorado, to see the stars and smell the air, but also to sleep with my first love, a gorgeous, blue Holubar bag bought for my foray into scouting.

Years later, after foolishly leaving that bag in the back of my pickup during a rainstorm, I moved on to a North Face Windy Gap bag. Then in 2015, after decades of loft-crushing use reduced its insulation capacity, I bought a lightweight REI Igneo 20-degree bag for my first long-distance hike, on the Colorado Trail; it’s still going strong (and my wife says I love it so much that it’s akin to infidelity).

Here’s the rundown on my newest sleeping accessory.

Big Agnes Torchlight UL 20º sleeping bag

Big Agnes Torchlight UL 20º

Big Agnes Torchlight UL 20-Degree At-a-Glance

MSRP: $399.95-$419.95
Temperature rating: 20 degrees F
Total weight: 36 ounces | 1,020 grams
Length: 70” (also available in 76”)
Adjustable circumference (regular size bag): shoulder, 60-70”; midsection, 54-64”; foot, 36-46”
Fill power: 850 Downtek water-repellent down
Fill weight: 17 ounces | 482 grams
Lining fabric: Lightweight polyester taffeta
Shell fabric: Ultralight ripstop water repellent polyester
Accessories: Storage sack and stuff sack


Let’s talk about that slickly designed system to provide restless sleepers like me (I am, one friend on the Appalachian Trail told me, a “rotisserie chicken sleeper,” constantly rolling from back to side to belly to side, all night long) with a little extra room.

big agnes torchlight ul 20

One of two 5-inch expandable side panels on the Torchlight UL 20º.

The Torchlight features two patent-pending, zippered panels from shoulder to foot box that add five inches of girth on each side when opened. There are zippers at each end of both panels, allowing for a bit of customization. I really love this feature; nothing more frustrating than trying to pull my knees up in a traditional mummy bag and becoming virtually stuck, a problem even with my beloved Igneo.

The jacket-style, contoured hood is nifty, too, featuring an adjustable cordlock and insulated bumper to keep out chilly drafts. The bumper along the main zipper is made from snag-resistant material, reducing the likelihood of an irritating fact of life in the era of super-lightweight materials. Among the many small, well-thought-out details is a zipper “garage” at the hood, so you won’t have to feel the cold bite of steel on your chin while sleeping.

Both inside and out, the Torchlight is extraordinarily silky and comfy. It’s like having your old childhood blankie back from the dead. The lining provides two more small, useful features: a mesh pocket at the shoulder for a phone, AirPods, and what have you; and fabric loops to help secure a liner. The exterior of the bag has several loops for easy hang drying or storage.

Despite the “UL” in its name, hard-core gram watchers won’t consider the Torchlight “ultralight,” but considering all its features, I think 2 pounds, 4 ounces is pretty light. That’s a full 7 ounces weightier than my 1-pound, 13-ounce Igneo, but I think the tradeoff–particularly in leg/knee room–is worth it.

The bag stuffs down to a relatively compact 5.5”x7”, hardly larger than my Igneo.

Versatility and Durability

big agnes torchlight ul 20

The Torchlight UL 20º is soft, silky and comfy. Jody Frank Evans photo.

I used the bag as follows:

  • 12 nights in my bed
  • 14 nights on the floor with my beloved Thermarest Z-Lite pad
  • 1 night cowboy camping south of Memphis, Tennessee (low temperature 68º F)
  • 1 night cowboy camping in Hackett, Arkansas (low temperature 60º F)
  • 1 night cowboy camping in Santa Rosa, New Mexico (low temperature 45º F)
  • 2 nights sleeping on my aunty’s back porch in Albuquerque (low temperature 65º F)
  • 1 night on the banks of Middle Cottonwood Creek, west of Buena Vista, Colorado (low temperature 37º F)
big agnes torchlight ul 20 jody frank evans

Jody Frank Evans photo.

None of that, obviously, tested Big Agnes’ claim that the bag will keep the average guy warm down to 18º F (28º F for women; temperatures assume the sleeper is wearing an under layer and hat). But I can tell you that it was plenty warm even in the mountains of Colorado, and it was clear that I would have remained snug in considerably colder temperatures. It bodes well that even cowboy camping on the high plains of eastern New Mexico, I was not just comfortable, but slept (as I often do) “quilt style,” with the bag unzipped and draped over me, so I can kick out a leg or arm to cool down during the night.

It’s hard to evaluate durability on an item you expect to last for years, but I’m consistently impressed by how sturdy many modern lightweight fabrics are, and Big Agnes is known for putting out tough gear. I expect my love affair to last for a long, long time.

Torchlight UL 20º Pros

Extra room: As noted above, this patent-pending design is perfect for anyone who doesn’t sleep like Count Dracula, on his back, perfectly still, hands neatly folded on his chest until it’s time to turn into a bat and terrorize the countryside. Honestly, even with the two expansion panels zipped up, the Torchlight provides more squirm- and knee-room than any other bag I’ve owned.

Warmth: If anything, the bag was a tad too warm for some of the conditions I’ve used it for. But even when on a long trail, I’ve never gone over to the quilt side, because it’s so easy to open up a bag and use it as a covering, rather than a bag. I’m eager to test it out down to 25 or 20º and fully expect it to keep me toasty all night long. I’m calling it a 3-season-plus bag.

Smart details: I love the expandable panels, the well-placed bumpers, the internal pocket and liner loops and zipper housing.

Multiple models: The four unisex and four women’s bags include a wide variety of choices in insulation, weight, and price.

big agnes torchlight ul 20 pocket

An internal mesh phone pocket is just one of several small, useful details the Torchlight UL 20º.

Torchlight UL 20º Cons

Price: There’s no question that this bag is a little pricier than most bags in its class, due to its extra features and water-resistant fill and fabric.

Weight: One time, a colleague at a newspaper where I worked wanted to try this sesame-mushroom salad dressing I’d brought for lunch. When she looked at the calories on the label, she freaked out and dropped the bottle (had I not told her I poured off most of the oil, I fear she would have expired). I imagine true ultralighters keeling right over upon reading that the Torchlight UL 20º tips the scales at a whopping 36 ounces. The “UL” is a tad misleading, given that the bag is just 7 ounces lighter than its non-UL Big Agnes analog.

Color: While pretty, the light silver and orange shell does tend to show the dirt when you are, well, sleeping in the dirt. The darker orange lining is better on this front.


rainbow lake colorado trail clay bonnyman evans

Rainbow Lake from the Colorado Trail. Clay Bonnyman Evans photo.

As I say, I’m head over heels. It really is the most comfortable sleeping bag I’ve ever had (I feel guilty writing that, imagining; but don’t worry, dear Igneo, I’m not leaving you, just going poly …). I do fret about those extra ounces (how many snapped-off toothbrush handles does it take to equal 7 ounces?) and if push came to shove, might consider leaving this beauty at home for a summer or early fall hike. Big Agnes makes smart, durable gear and I fully expect to be using the Torchlight for many years to come.

Shop the Torchlight 20 at REI Shop the Torchlight 20 at Backcountry

Comparable Products

REI Co-op Magma 15

MSRP: $379-$399
Weight: 28 ounces (1 pound, 12 ounces)
Girth: shoulder, 63 inches; hip, 57 inches

NEMO Disco 15

MSRP: $299.95-$319-95
Weight: 43 ounces (2 pounds, 11 ounces)
Girth: shoulder, 64 inches; hip, 59 inches

Western Mountaineering UltraLite 20

MSRP: $510-$540
Weight: 29 ounces (1 pound, 13 ounces)
Girth: shoulder, 59 inches; hip, 51 inches

This product was donated for purpose of review

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Comments 4

  • Bendik : Dec 28th

    I put this bag on my wishlist after reading your review. When I got it for christmas, I immediately tested it by sleeping outside on christmas eve. I live in Norway and slept comfortably under an open sky in -3 C (26.6 F), and I was toasty and bare naked. I agree with you that the liner is extremely comfortable, and it feels like the whole bag is just barely touching my skin instead of weighing me down while I sleep. The bag is extremely fluffy! So far I am very satisfied, but if I had to point out a con, it would be that the zipper tends to get a bit stuck, but hey, that’s no biggie is it?

    It is so comfortable that I actually ended up using the bag instead of my duvet. Might have to change the duvet then…

    Thank you for your great review!

    • Clay Bonnyman Evans : Dec 28th

      Glad you found the review helpful.

      I love the Torchlight UL 20 — by far the comfiest bag I’ve ever had!




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