Feathered Friends Swallow UL 20 Review

Given Feathered Friends’ history of keeping me toasty in chilly conditions, their Swallow UL 20 was at the top of my list for options when hiking Vermont’s Long Trail last September. The older I get, the less excited I become at the prospect of fussing with a quilt, especially when temperatures are expected to dip below freezing.  The Swallow’s no frills mummy design was, on paper, exactly what I wanted for this hike.

Feathered Friends Swallow UL 20 Sleeping Bag At a Glance

Length: 6’0″ (Regular)
Fill Power: 950+ Goose Down
Fill Weight: 16.7 oz / 476 g
Total Weight: 27 oz (1 lb 11 oz)
Shell Fabric: Pertex® Endurance® UL 10 denier
Lining Fabric: Flite 15 denier ripstop nylon
Zip Side: Left
Manufactured in the USA (Seattle, Washington)
MSRP: $529.00

Best Use

This sleeping bag is a great option for those who have an ambitious three-season backpacking bucket list.  This bag is rated at 20 degrees, and although I have not tested it in temperatures below this rating, I’ve seen plenty of nights below freezing, and have stayed sufficiently warm.  Quilts are a great option for back sleepers and those who don’t toss and turn throughout the night.  I am not one of those people, and thus appreciate the full coverage that a mummy bag provides.  Given the price tag of the Swallow, this bag makes sense for someone who will get ample use out of a UL, high-quality bag.  For car campers and weekend warriors, I would suggest something cheaper (and consequently heavier).

Circumstance of Review

This bag was used for the duration of my 2019 Long Trail NOBO thru-hike and several shorter trips since, including a recent hike of the Four Pass Loop between Aspen and Crested Butte (~30 miles).  With a relatively short window—I hiked the Long Trail in 15 days vs. the 20-30 day average (according to the GMC)—I needed a light setup yet something that would suffice in Canada’s underbelly (aka northern Vermont) in late September.


One of my favorite features of this bag is its lack of features.  Many bags sold at big retailers try to differentiate their products with features that are excessive, add weight, yet lack the quality materials used on top quality bags, such as this one.  That said, there are a few items worth highlighting.

Passive Collar

A fancy term for “warm tube around the hood.”  This is in place to prevent heat from escaping.  A penny saved is a penny earned, and when it comes to sleeping in frigid temperatures, heat is way better than pennies.

Trapezoidal Footbox

A lot of brands claim a trapezoidal footbox.  Feathered Friends’ is a tad roomier than some other brands that I’ve tested.  If you sleep on your back without tossing and turning, you could get away with a more narrow footbox. I appreciate the extra wiggle room.

Continuous Baffles

A feature that’s pretty ubiquitous among all top quality bags and quilts that allows you to reposition down (by shaking + shimmying) to better control your bag’s insulation.  In reality, it’s much easier to control your temperature by (un)zipping your bag to tweak airflow, but the idea that you can do this might be fun for some.

3D Contoured Hood

Again a fancy term that means “big hood” to prevent overheating in warmer conditions and a drawstring to cinch down when temperatures drop.

Draft Tube

Like the passive collar, this is another “warm tube” that follows the bag’s zipper.  If you’ve ever felt cold air entering from the zipper area of a bag, you will be a big fan of this particular warm tube.

#5 YKK Two-Way Separating Zipper

I’m no zipper expert, but the large plastic separating attachment on the top zipper does a bang-up job of preventing fabric snags. Ripping your sleeping bag’s face or lining fabric while zipping up in the middle of the night is a misery you’d rather avoid. The extreme weight weenies out there might prefer a bag with a simpler zipper setup.


Not a listed feature, but one thing I like about Feathered Friends’ lineup is the variety of models in a given temperature range.  The Swallow is their middle-width (not to be confused with Middleditch) 20-degree (or 30-degree) option, with the Hummingbird being the narrowest, and the Swift being the widest.  The skinny hikers out there might prefer the Hummingbird, while my bigger-boned buds might opt for the Swift.



As mentioned previously, this thing stood up to the task of keeping ole’ Badger comfortable throughout his time jaunting across the state of Vermont.  The idea of being a stone’s throw from Canada in (potentially) October was an anxiety inducing thought during my preparation.  Not once did I have that unmistakable “I must wear every article of clothing, sleep face down to utilize my breath as a man-made heater, and pray to Zeus” moment, which was nice.  The few features that this bag provides are aimed toward ensuring a warm night’s sleep.  A thoughtful design that doesn’t incorporate gimmicky tricks.  In the context of backpacking, though, warmth matters very much relative to…


Finding a true 20-degree bag that’s comfortable for a wide-torso body like mine at under two pounds is nothing shy of Hiker Trash Euphoria.  950+ fill power down is as good as it gets, and Feathered Friends does not skimp on the filling with this bag.  For a backpacker who’s not ultra-price sensitive, warmth and weight are going to be by far and away the two biggest considerations, and the Swallow knocks it out of the park.  Small tweaks, such as the zipper setup, face fabric, etc., could be altered to drop even more weight (likely grams instead of ounces), but at this price point, you want to be sure you’re getting something that’s going to hold up for thousands of miles.  I’m only a few hundred miles deep, but it’s still in like-new condition.


As mentioned above, there are lighter 20-degree bags on the market (though not by a lot), though I question if there are any that are more durable given the materials used on this bag.  Weigh in in the comments because if so, I would like to know.  The shell fabric features a heavier denier than some other alternatives, which is going to provide great durability at the cost of weight and packability.  If you don’t want to have to worry about babying your bag, this is a trade-off you should favor.

Made in the USofA

Probably needs no explanation on why this is a pro, unless you’re reading this from a different country, in which case, please let me know if I can please crash on your couch during future travels.  You can read about Feathered Friends’ warranty here.



The price tag of this thing is going to be disqualifying for some people, which is totally fine.  That said, I always encourage people to adjust their gear budget to favor buying quality across your big three (plus footwear).  With sleeping bags and quilts, you get what you pay for, and you’re paying for a UL, three-season bag that’ll likely last you a couple of presidential administrations at least.


I’ve seen others comment about the compressibility of this sleeping bag.  As far as I can tell, that’s a byproduct of a healthy serving of very high fill power loft.  Small features like the big zipper, drawstring, and button closure at the hood do add a little bulk (and weight), but what makes this bag occupy the space that does is the very same feature that makes it insulate so well.  I had no problem getting this into my 40-liter pack without a compression sack, though I did rip through an 8L stuff sac in the process of trying to compress it fully (this sac was also many years old and likely overdue for failure).  The denier of the shell and interior fabric is right in line with what’s offered from other high end, quality brands such as Western Mountaineering.



Many of Feathered Friends’ other bags use a Pertex Y Fuse face fabric, which is slightly more breathable compared to the Pertex Endurance UL, however, not as a light.  I haven’t had an issue with the breathability of this bag; the loft is still very lofty, but I have yet to encounter a particularly warm night during my time with the Swallow.  I will update this section if that changes with more use, but a rep at Feathered Friends cited that the only downside would be “a slight reduction in tear strength and breathability relative to the YFuse fabric.”


If the price of the Swallow isn’t disqualifying, you should give strong consideration to the Swallow, as you’ll be hard pressed to do better for a three-season bag.  This has become my go-to option for most of my backpacking trips, especially if temperatures are expected to approach or dip below freezing.  I’ve had nothing but great experiences with Feathered Friends sleeping bags, and the Swallow is no exception.

Shop The Feathered Friends Swallow UL 20/30 here

Comparable Sleeping Bags

Western Mountaineering UltraLite 20F

MSRP: $525
Fill Power: 850-fill down
Fill Weight: 16 oz
Total Weight: 1 lb 13 oz

Marmot Helium Down Sleeping Bag

MSRP: $412
Fill Power: 800-fill down
Fill Weight: 19.8 oz
Total Weight: 2 lb 1 oz

Enlightend Equipment Convert

MSRP: $480
Fill Power: 950-fill down
Fill Weight: 16.05 oz
Total Weight: 1 lb 8.64 oz

Disclosure: This item was donated for the purpose of this review, which affects my opinion precisely none percent.

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Comments 2

  • Susan : Aug 4th

    I think my FF bag is a Hummingbird, not sure the rating; I have loved my Feathered Friends since 2006. I’ve used it on several long distance and cold backpack trips. I share time with one other bag, western mountaineering rated 10degree.


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