Feathered Friends Swallow UL 20 review

The Swallow UL 20 is the lightest and most premium bag here. Feathered Friends lists an average weight of 1 lb 10.6 oz (754 g) for the Regular, with 1 lb 0.8 oz of 950+ fill power goose down, all RDS-certified. The shell is Pertex Quantum Pro, a water-resistant and breathable fabric, with a DWR made without intentionally added PFAS, and the footbox lining uses Pertex Diamond Fuse to resist wear from hiker feet. The mummy shape measures 59 inches at the shoulder and 64 at the elbow, with a contoured hood and a generous draft tube behind a two-way #5 YKK separating zipper. Each bag is finished by hand in Seattle, which is why the company quotes 7 to 10 days to ship. The rating is 20°F, but Feathered Friends does not publish separate ISO comfort and limit numbers, so it is harder to compare directly. At $659 it is the most expensive choice, and the value score reflects that.

Who it is for

ultralight backpackers who will pay for the lightest 20°F bag

Price

$659 for the 20 degree Regular at the Feathered Friends store when checked.

Regular price $659.00
Quoted from the vendor pricing page on November 12, 2026.

Key features

• 950+ fill power goose down, 100% RDS
• 1 lb 10.6 oz (754 g) average weight for the 20°F Regular
• Pertex Quantum Pro shell with a PFAS-free DWR
• Pertex Diamond Fuse footbox lining for abrasion resistance
• Made in Seattle; two-way #5 YKK separating zipper

Strengths and weaknesses

• Strength: The lightest 20°F bag on this list at 1 lb 10.6 oz
• Strength: Highest fill power here at 950+
• Strength: Also sold as a 30°F version from $599
• Weakness: $659 is the highest price on this list
• Weakness: Feathered Friends says bags ship in 7 to 10 days because they are finished to order
• Weakness: Publishes a single temperature rating rather than ISO comfort and limit figures

Key facts

• Price: $659 (20°F Regular)
• Temperature rating: 20°F / -6.67°C
• Weight: 1 lb 10.6 oz (754 g)
• Insulation: 950+ fill goose down
• Made in: Seattle, USA

Where it ranks

Feathered Friends Swallow UL 20 is No. 3 in our Best Sleeping Bags verdict.