Compare temperature ratings, fill type, weight and packed size
High fill-power down bags made in the USA
850+ fill power goose down across the rangeContinuous baffles let you shift down by seasonAmong the lightest bags at a given temperature ratingMade in California with a lifetime workmanship warrantyPremium pricing and limited discounting
Seattle-made down bags with heavy overfill
900+ fill power down on the flagship bagsGenerous overfill for genuine cold-weather useWater-resistant shell fabrics availableSewn in Seattle with a lifetime workmanship warrantyLong lead times on some models
Own-brand bags with third-party tested ratings
Down and synthetic options at moderate pricesTemperature ratings tested to the ISO standardResponsible Down Standard certified fillOne-year returns policy for co-op membersWide range of sizes and zipper configurations
Spoon-shaped bags for side sleepers
Wider at elbows and knees for side sleepingThermo Gills vent heat without opening the bagDown and synthetic lines availableLifetime warranty against defectsBulkier packed size than a strict mummy cut
Compact down bags and quilts with clear rating data
ISO tested comfort and limit figures publishedUltra-Dry treated down on most modelsQuilt and half-zip options to cut weightVery small packed size for the warmthCompression sack included with most bags
Widely stocked bags from entry level to expedition
Range spans car camping to high-altitude bagsSynthetic options that stay warm when dampEasy to find in physical stores and try in personLifetime warranty on materials and workmanshipWarm-weather models are heavier than specialist rivals| Product | Western Mountaineering 9.6 | Feathered Friends 9.2 | REI Co-op 8.7 | Nemo Equipment 8.3 | Sea to Summit 7.8 |
|---|---|---|---|---|---|
| Highlights | 850+ fill power goose down across the range · Continuous baffles let you shift down by season · Among the lightest bags at a given temperature rating · Made in California with a lifetime workmanship warranty · Premium pricing and limited discounting | 900+ fill power down on the flagship bags · Generous overfill for genuine cold-weather use · Water-resistant shell fabrics available · Sewn in Seattle with a lifetime workmanship warranty · Long lead times on some models | Down and synthetic options at moderate prices · Temperature ratings tested to the ISO standard · Responsible Down Standard certified fill · One-year returns policy for co-op members · Wide range of sizes and zipper configurations | Wider at elbows and knees for side sleeping · Thermo Gills vent heat without opening the bag · Down and synthetic lines available · Lifetime warranty against defects · Bulkier packed size than a strict mummy cut | ISO tested comfort and limit figures published · Ultra-Dry treated down on most models · Quilt and half-zip options to cut weight · Very small packed size for the warmth · Compression sack included with most bags |
Editorially scored by our research team.
Every score out of 10 is assigned by our editors from published pricing, features, fees, coverage and support terms — not from user-submitted reviews. Scores are our own opinion and change as products change. Read our full methodology.
Western Mountaineering is our top-scoring pick in Sleeping Bags, at 9.6/10 — it highlights “850+ fill power goose down across the range”.
Feathered Friends scores 9.2 and is the one to compare against it — it highlights “900+ fill power down on the flagship bags”.
Both scores are our editors’ assessment of published specifications, pricing and terms against the criteria in our rating methodology — they are not aggregated customer reviews.
Almost every complaint about a sleeping bag traces back to reading the wrong number on the label, so start here.
Bags tested to the ISO standard publish two figures. The comfort rating is the temperature at which a person who sleeps cold can rest comfortably. The limit rating is where a person who sleeps warm can sleep curled up without waking. They are typically about 10 °F apart.
Marketing usually quotes the limit figure, because it is the lower and more impressive one. For most people the comfort rating is the honest number. Treat a "20-degree bag" as a bag you will be comfortable in somewhere nearer 30 °F unless the label says otherwise.
There is also a survival or extreme rating on some labels. It describes preventing hypothermia, not sleeping. It should play no part in choosing a bag.
Not every brand tests to the standard. If a bag lists a single number with no mention of ISO or EN testing, that figure is the manufacturer's own opinion and is not comparable with a tested one.
Down gives more warmth per ounce and per litre of pack space than anything else, and a good down bag lasts decades if you store it uncompressed. Its weakness is water: wet down clumps and stops insulating. Hydrophobic treatments delay that but do not eliminate it.
Synthetic fill keeps a useful amount of warmth when damp, dries faster and costs less. It is heavier and bulkier at the same rating, and it loses loft over the years as the fibres break down.
The rule of thumb that holds up: choose down for cold and dry, synthetic for wet and mild, and for anything you expect to stuff into a wet canoe.
Fill power measures down quality — the volume one ounce of down occupies. 850 fill power down lofts more than 650, so a bag needs less of it for the same warmth and comes out lighter and smaller. It also costs considerably more. Fill power describes quality; total fill weight describes how much is in the bag. A high fill power with a small fill weight is a light bag, not necessarily a warm one.
Warmth comes from your body heating the air inside the bag, so dead space costs you warmth.
Mummy bags are cut close, with a hood that cinches around your face. They are the warmest and lightest for a given amount of fill, and the most confining.
Rectangular bags are roomy and often unzip into a quilt. They are heavy and bulky, which is fine if the bag lives in a car and never on your back.
Modified or spoon shapes widen at the elbows and knees. If you sleep on your side and have found mummy bags intolerable, this shape is the reason to look again.
Quilts remove the insulation underneath, which your body weight flattens uselessly anyway, and attach to your sleeping pad instead. They save meaningful weight for people who do not roll around much.
This is the part most buyers get wrong. Compressed insulation under you does almost nothing, so on cold ground the pad — not the bag — determines whether you are warm.
Pads are rated by R-value, a straightforward measure of resistance to heat loss. Roughly: R-2 for summer, R-4 for three-season, R-5 and up for snow. Pairing a serious winter bag with a thin summer pad is the single most common cause of a cold night, and no amount of extra down fixes it.
A sleeping bag stored compressed in its stuff sack loses loft permanently, and loft is warmth. Store it in the large cotton or mesh sack that comes with it, hanging or loose in a cupboard, and use the compression sack only while travelling. This single habit does more for a bag's working life than anything else, and it is why a decade-old bag from a careful owner often outperforms a three-year-old one that lived in its stuff sack.
Wash it rarely, with a down-specific or technical wash, and dry it on low heat with dryer balls to break up clumps. A liner is easier to wash than the bag and keeps body oils off the fill.
Several brands here offer lifetime warranties against defects in materials and workmanship — which covers a failed zipper or a split seam, not the bag wearing out or a tear from a stray ember. More useful in practice is whether the company will repair a bag for a fee. A brand with a repair department is worth paying more for on an item you intend to keep for twenty years.