Best Sleeping Bag for Winter Camping: 10 UK Picks (2025)

Winter camping in Britain is as much damp air and biting wind as sub‑zero cold. A night on a high pitch in Snowdonia or a still bothy in the Cairngorms can turn miserable fast if your bag is the weak link: clammy fabric, compressed fill, cold feet and no sleep. Choosing well isn’t easy either: comfort vs limit ratings, down vs synthetic, hydrophobic treatments, weight and pack size, cuts for different bodies, and price.

We’ve shortlisted ten of the best winter bags you can buy in the UK for 2025, tested and benchmarked for real British conditions. From ultralight high‑camp choices to warm, great‑value workhorses and wet‑weather synthetics, each pick covers what it’s best at, temperature and insulation, true weight and pack size, fit notes, standout features, and UK pricing with where to buy. We’ll also decode the jargon so you know what to expect on a frosty night. First up: our editor’s pick, the Therm‑a‑Rest Parsec -18.

1. Take a Hike UK editor’s pick: Therm-a-Rest Parsec -18

If you want a proven, UK-ready winter bag that balances real warmth, low weight and sensible features, the Therm-a-Rest Parsec -18 is the one to beat. Tested by The Great Outdoors, it hits that sweet spot for British winters: warm at camp, light in the pack, and built with weather-aware details that fend off damp and drafts.

Why it’s great

The Parsec feels purpose-built for long, cold UK nights. Reviewers found it warm, comfortable and impressively light for the performance, with a smart mummy cut that still gives room at the shoulders for side or front sleepers. Hydrophobic down, a big draft collar and a cinchable hood keep heat where it matters, and you’re not fighting snags thanks to a well-executed main zip.

Temperature and insulation

Comfort-rated to -10°C (manufacturer rating cited by The Great Outdoors), the Parsec -18 uses 800 fill power, Nikwax-treated, RDS-certified down in heat-mapped zones to maximise warmth where your body needs it most. The hydrophobic treatment helps the down resist moisture and dry faster, a real advantage in damp UK conditions and condensation-prone tents.

• Insulation: 800 FP Nikwax hydrophobic RDS down
• Rating (comfort): -10°C
• Construction: Heat-mapped zoning, substantial draft collar and draft tube

Weight, pack size and fit

At 1,127g (regular), the Parsec is properly light for a true winter bag. It ships with an 88g stuff/compression sack; note the tall, narrower sack shape can be a touch fiddly to pack tightly. Fit-wise it’s a unisex mummy with a slightly broader shoulder cut that works well for side or front sleepers. Removable mattress straps stabilise the bag on your pad (best with mats up to 3 inches thick).

• Measured weight (regular): 1,127g (bag) + 88g (sack)
• Length (regular): 183cm
• Fit notes: Roomier shoulders; secure to-mat straps for a twist-free night

Standout features

The Parsec’s feature set is dialled for winter without gimmicks, and every detail helps you stay warm, dry and organised.

• Insulated foot pocket: Extra warmth where many campers lose heat first
• Large draft collar + draft tube: Serious protection against heat-robbing gaps
• Anti-snag, 2-way, 3/4-length zip: Vent where you want; fewer midnight battles
• Hydrophobic down + recycled shell: Real-world moisture resilience and eco creds
• External pocket: Quick access for a headtorch or battery
• Mat-attachment straps: Keep the bag centred on your pad (≤3" thick for best fit)

Who it’s for

• UK winter wild campers and bothy goers who want reliable sub-zero comfort without carrying a 1.5kg+ bag.
• Side/front sleepers who appreciate a bit more shoulder room in a mummy.
• All-rounders seeking one bag to span deep autumn to proper winter trips; ideal as a best sleeping bag for winter camping in typical British conditions.

UK price and where to buy

• Price (UK): £459 (as listed by The Great Outdoors review)
• Sizes: Small, Regular (183cm), Long
• Availability: Widely available via Therm-a-Rest’s UK channels and major outdoor retailers across the UK.

2. Rab Mythic 600: ultralight warmth for high camps

When weight really matters on a big winter day and you still need dependable warmth, the Rab Mythic 600 is a standout. Tested by The Great Outdoors and crowned “best for high camps”, it pairs elite-quality down with a stripped-back feature set to deliver serious performance under a kilo.

Why it’s great

Rab uses exceptionally high-loft 900 fill power European goose down with a Nikwax fluorocarbon‑free hydrophobic treatment, wrapped in a 10D recycled Atmos shell with FC‑free DWR. Reviewers noted superb loft, excellent compressibility, strong DWR resistance before wetting out, and a minimalist, no‑nonsense build that keeps grams off your back while staying warm on exposed pitches.

Temperature and insulation

With a comfort rating of -5°C, limit of -12°C and extreme of -32°C, the Mythic 600 is dialled for typical UK high-camp temperatures, with reserve when paired with clothing. Its chevron trapezoidal baffles control down migration and maximise loft across the torso and legs, while the hydrophobic finish helps maintain performance in damp, condensation-prone shelters.

• Fill: 600g of 900FP European goose down (Nikwax hydrophobic)
• Ratings (ISO): Comfort -5°C; Limit -12°C; Extreme -32°C
• Baffles: Chevron trapezoidal; full zip baffle; shoulder baffle

Weight, pack size and fit

At a quoted 886g, the Mythic 600 is genuinely ultralight for a winter‑capable bag. TGO measured an impressively small packed size around 20×23cm in a standard sack and noted it could compress further. The cut is an efficient mummy suitable for fast-and-light use, with an adjustable hood and shoulder baffle to fine‑tune the seal.

• Weight: 886g (bag)
• Length: 215cm (unisex, one size)
• Pack size: Extremely compressible; ~20×23cm observed in test

Standout features

• Premium down, premium loft: 900FP European goose down for top warmth‑to‑weight
• Weather-aware build: 10D recycled Atmos shell with FC‑free DWR
• Moisture resilience: Nikwax hydrophobic down retains loft longer when damp
• Efficient closure: ¾ two‑way zip with draft tube for venting and protection
• Heat management: Adjustable hood and shoulder baffle to lock in warmth
• Minimalist extras: Hanging loops and clean design to keep weight to a minimum

Who it’s for

• Alpinists and gram‑counters chasing sub‑kilo warmth for UK winter high camps.
• Experienced winter backpackers who understand ISO ratings and will layer intelligently below the -5°C comfort mark.
• Anyone wanting the best sleeping bag for winter camping where pack weight and compressibility are critical.

UK price and where to buy

• Price (UK): £660 (as listed by The Great Outdoors)
• Spec: Unisex, one size (215cm)
• Where: Available direct from Rab and through specialist UK outdoor retailers.

3. Mountain Equipment Glacier 700: dependable 4-season for UK hills

The Glacier 700 is a classic, no‑nonsense winter bag that’s become a staple on UK hills for a reason. Tested by The Great Outdoors and recommended by Peter Macfarlane, it delivers instant warmth, robust weather resistance and a trustworthy build without needless frills. If you want a dependable four‑season option for British winters, this is a strong contender for the best sleeping bag for winter camping.

Why it’s great

Performance is the Glacier 700’s calling card. Reviewers found it one of the warmest in its group, with fast “feedback” the moment you climb in and a shell that resists wetting out impressively in damp tent interiors. The design is clean and durable, with just the right adjustments where they matter and little to go wrong in foul weather.

Temperature and insulation

Mountain Equipment stuffs the Glacier 700 with 699g of minimum 700 fill power, Down Codex‑approved duck down. Trapezoidal and slanted box‑wall baffles control migration and maximise loft, backed by zip, hood and shoulder baffles to seal in heat. The ISO‑style ratings quoted by TGO put it at a comfort of -6°C, limit of -13°C and extreme of -34°C—ideal for typical UK winter camps, with extra layers covering colder snaps.

• Fill: 699g, 700+ FP duck down (Down Codex approved)
• Ratings: Comfort -6°C; Limit -13°C; Extreme -34°C
• Baffle design: Trapezoidal/slanted box walls with full draft protections

Weight, pack size and fit

At 1,180g (regular), the Glacier 700 is a sensible carry weight for true winter. Compressed, it slots neatly into a pack at around 20×25cm—compact for the warmth on offer. The cut is a close, efficient mummy: cosy and thermally effective, but movement—especially bending a knee—can feel a touch restricted compared to roomier bags. Available in regular and long lengths.

• Weight (regular): 1,180g
• Compressed size: ~20×25cm (measured in test)
• Fit notes: Close cut; warm and efficient, slightly limiting for restless sleepers

Standout features

• Weatherproof shell: DRILITE LOFT outer with FC‑free DWR; recycled inner fabric
• Thermal sealing: Adjustable hood and shoulder baffle plus zip baffle
• Reliable closure: ¾ two‑way zip for venting and easy entry
• Ethical down: Mountain Equipment’s Down Codex traceability
• Minimalist practicality: Clean exterior, simple hang loop for drying

Who it’s for

• Hillwalkers and bothy regulars wanting a robust, four‑season bag that shrugs off damp and delivers consistent warmth.
• Backpackers who value proven performance over ultra‑minimal weight.
• Snug‑mummy fans: If you prefer an efficient, close cut over sprawling room, this fit works brilliantly.

UK price and where to buy

• Price (UK): £400 (regular)
• Sizes: Regular (205cm) and Long; men’s and women’s versions available
• Availability: Widely available via Mountain Equipment’s UK stockists and specialist outdoor retailers nationwide.

4. PHD Greenlandic 500: custom-build warmth made in the UK

A favourite of serious winter backpackers, the PHD Greenlandic 500 combines ultra‑premium 950 fill power European goose down with bespoke sizing options to deliver a remarkable warmth‑to‑weight ratio. Tested by The Great Outdoors, it’s praised for outright toastiness and low mass, with the ability to tailor length and width so you get a dialled fit rather than hauling surplus fabric. If you’re hunting the best sleeping bag for winter camping without carrying a kilo and a half, this is a compelling route.

Why it’s great

The Greenlandic 500’s core appeal is simple: elite down, efficient construction and custom sizing that wastes neither grams nor warmth. Reviewers highlight how quickly it feels warm inside and how hard it is to beat for warmth per gram. It’s a minimalist design that focuses on performance, not gimmicks.

Temperature and insulation

PHD rates the Greenlandic 500 to a comfort of -10°C. The company uses 950 FP goose down and adjusts fill amounts across the size and width range to maintain that warmth rating, so you don’t lose performance by choosing a longer or wider build. Straight wall baffles keep the down stable, while PHD’s “Ultrashell” rip‑stop nylon adds a protective outer.

• Fill: 950 FP European goose down
• Comfort rating: -10°C
• Construction: Straight wall baffles; Ultrashell outer; 7X rip‑stop lining

Weight, pack size and fit

Despite real winter credentials, quoted weight starts from 890g, with the tested spec at 965g. The cut isn’t expansive—there’s wriggle room, but drawing knees fully up can feel a bit constraining—helping thermal efficiency. Note that PHD does not include a compression sack; if you want a tiny pack size, you’ll need to supply your own.

• Weight: From 890g (tested around 965g)
• Fit options: Standard, Short, Long, Extra Long; Slim‑fit, Wide, Extra Wide
• Packability: Very compressible down (compression sack not supplied)

Standout features

• Custom build: Multiple lengths and three widths for a made‑to‑measure feel
• Elite insulation: 950 FP down for exceptional loft and fast warmth
• Efficient closure: Simple 1‑way half‑zip reduces weight and cold spots
• Low‑bulk shell: Ultrashell rip‑stop nylon balances protection and grams
• Simplicity first: Minimal trims; basic top tab/Velcro; no shoulder baffle

Who it’s for

• Weight‑conscious winter backpackers who want maximum warmth per gram.
• Shoppers who struggle with standard fits, and value length/width options.
• Experienced users comfortable with a minimalist feature set and managing drafts without a dedicated shoulder baffle (e.g., pairing with clothing).

UK price and where to buy

• Price (UK): From £792 (spec‑dependent)
• Sizes: Standard, Short, Long, Extra Long; Slim‑fit, Wide, Extra Wide
• Availability: Available from PHD with configurable size and width options.

5. Nemo Sonic -20: for deep-freeze missions

If your winter itinerary includes true sub-zero overnights, the Nemo Sonic -20 is built for confidence. Awarded “best bang for the buck” by independent testers, it combines impressive warmth, moisture management and smart venting that widens its usable range—exactly what you want when Scottish nights swing from bitter to merely brisk.

Why it’s great

Testers rate the Sonic as one of the warmest bags in its class and—crucially—easy to live with across changing conditions. Hydrophobic down, a water‑resistant shell and a well‑designed hood/neck gasket help keep damp at bay, while the bag’s unique upper vents let you dump heat fast instead of sweating into your insulation. That balance is rare at this temperature rating and price point.

Temperature and insulation

The Sonic carries a -20°F (-28.9°C) advertised rating and has proven trustworthy in the field down to around -10°F (~-23°C) when used thoughtfully. Its 800 fill power, PFC‑free hydrophobic down delivers serious loft, and the thermal efficiency is boosted by a cinchable face/neck gasket plus a proper zipper draft baffle.

• Fill: 800 FP hydrophobic, PFC‑free down
• Advertised rating: -20°F (-28.9°C)
• Real‑world range: Comfortable for testers to ~-10°F with good technique
• Moisture control: DWR shell and waterproof footbox protect key areas

Weight, pack size and fit

This isn’t the lightest deep‑winter option, but its numbers are honest for the warmth it provides. Measured at 1.68kg (regular) with a packed volume around 16.5 litres, it’s carryable for multi‑day missions. The cut is thermally efficient; taller users (around 183cm/6ft) may prefer the long size to avoid compressing the footbox.

• Measured weight (regular): 1.68kg
• Measured packed volume: ~16.5 litres
• Fit notes: Streamlined; consider sizing up if you’re near the height limit

Standout features

• Thermo‑regulating vents: Upper zippered vents expand comfort into milder nights
• Waterproof footbox: Guards against tent condensation and damp fabric contact
• Face/neck gasket: Cinches to seal precious warmth in high winds
• Draft protection: Substantial zipper baffle reduces cold spots
• Weather‑aware shell: 20D recycled, bluesign‑approved ripstop with DWR
• Quality build: Thoughtful hood design and reliable hardware

Who it’s for

• Winter backpackers and mountaineers who prioritise security in genuine deep freeze.
• Cold sleepers seeking a best sleeping bag for winter camping that won’t blink when temperatures plunge.
• UK Highland high‑campers who value moisture management as much as raw warmth—even when tents bead with condensation.

UK price and where to buy

• List price: $660 (manufacturer list; regional pricing varies)
• Sizes: Short (5'6"), Regular (6'), Long (6'6")
• Availability: Widely stocked by specialist outdoor retailers; check UK dealers for current GBP pricing and size availability.

6. Sierra Designs Nitro 0°: best value down winter bag

If you want genuine winter warmth without a premium price, the Sierra Designs Nitro 0° is the bargain that keeps showing up on cold UK camps. The Great Outdoors named it “Best value,” and for good reason: lofty 800‑fill hydrophobic down, a sensible winter feature set, and a weight that won’t punish your pack.

Why it’s great

The Nitro 0° punches well above its price with real warmth and a clever design. Testers highlighted how toasty it feels for cold‑sleepers, crediting a generous draft collar, proper zip draft tube and a warm, easily adjusted hood. Its party trick—the self‑sealing foot vent—lets you dump heat fast without fiddling with zips, widening its usable range across changeable British winters.

Temperature and insulation

With a comfort rating of -9°C, the Nitro is a bona fide winter bag for the UK. Sierra Designs uses 736g of 800 fill‑power, hydrophobic DriDown that holds loft better in damp, condensation‑prone tents. A thin but durable 15D ripstop shell keeps weight down while boxy baffle construction and a half‑length zip reduce cold spots.

• Fill: 736g 800 FP hydrophobic DriDown (duck)
• Comfort rating: -9°C
• Shell: 15D ripstop nylon
• Thermal guards: Full draft collar and zip draft tube

Weight, pack size and fit

At 1,250g (regular), the Nitro is light for a true winter performer and compresses well thanks to high‑loft down and a 15D shell. The 198cm length (regular) offers decent interior space for a standard mummy cut, with an easy‑to‑cinch hood that seals snugly on blustery nights. Note the half‑length zip saves weight, but limits venting options versus full‑length designs.

• Weight (regular): 1,250g
• Length (regular): 198cm
• Fit notes: Classic mummy; cosy hood; no internal pocket

Standout features

• Self‑sealing foot vent: Kick heat fast without opening zips; reseals when you relax
• Generous draft collar: Stops warm air leaking at the shoulders
• Two‑way half‑length zip: Weight‑saving closure with a proper draft tube
• Hydrophobic down: Better performance when tents bead with condensation
• Warm, simple hood: Easy adjustments from inside the bag

Who it’s for

• Value‑minded winter backpackers who want a credible best sleeping bag for winter camping without spending £500+.
• Cold‑sleepers who’ll appreciate the stout collar and efficient baffle layout.
• Mixed‑conditions campers who like the foot vent for milder overnights and bothy trips.

UK price and where to buy

• Price (UK): £324.99 (Decathlon listing); $359.95 RRP
• Sizes: Regular and Long; men’s and women’s versions available
• Availability: Commonly stocked at Decathlon and specialist outdoor retailers across the UK.

7. Sea to Summit women’s Ascent -9C: best women’s all-rounder

A rare mix of real winter warmth, low weight and everyday usability, the Sea to Summit Women’s Ascent -9C stood out in The Great Outdoors’ tests as both the Lightest in Test and Fiona Russell’s Best in Test 2025. It’s a women-specific cut that’s genuinely comfortable, properly warm, and versatile enough to cover three‑season trips and deep winter camps with smart venting.

Why it’s great

Testers praised the Ascent’s warmth, fit and versatility. The women’s shape is wider at the hips and a touch narrower at the shoulders, which feels natural and still leaves room to wriggle or curl up. Build quality is excellent, with hydrophobic down and weather‑aware fabrics that handle damp UK conditions well. If you want one bag to span October to March, this is a top candidate for the best sleeping bag for winter camping.

Temperature and insulation

Comfort‑rated to -9°C (limit -15°C), the Ascent uses high‑quality 750+ fill power, RDS‑certified goose down with Sea to Summit’s Ultra‑Dry Down treatment to resist moisture and dry faster. Box‑wall construction with vertical chest baffles keeps loft where you need it most, while horizontal lower baffles minimise cold spots.

• Insulation: 750+ FP RDS goose down, Ultra‑Dry Down treated
• Ratings: Comfort -9°C; Lower limit -15°C
• Baffles: Box wall; vertical torso baffles; horizontal lower half

Weight, pack size and fit

At just 797g, it’s exceptionally light for a true winter‑capable women’s bag. It compresses neatly in the supplied sack, and Sea to Summit also includes a separate zipped storage bag. The women’s regular fits up to 170cm; the long up to 185cm. Inside, it feels roomy enough to shift position without losing thermal efficiency.

• Measured weight: 797g (bag)
• Sizes: Regular 170cm; Long 185cm
• Packability: Compresses to a tidy, backpack‑friendly bundle

Standout features

The Ascent is loaded with practical touches that expand its usable range and fend off drafts and damp.

• Triple 2‑way zips: Full‑length, half‑length and toe‑box zips for precise venting
• Weather protection: Recycled 20D shell; 10D waterproof‑breathable hood and footbox
• Draft control: Well‑shaped hood and effective draft guards
• Eco creds: RDS down and recycled main fabrics
• Storage: Comes with a compression sack and a zipped storage bag (small internal pocket is, admittedly, tiny)

Who it’s for

• Women who want one-bag versatility across UK shoulder seasons and winter.
• Backpackers who value low carry weight without sacrificing warmth.
• Side and curl‑up sleepers who prefer a women‑specific fit with room to move.

UK price and where to buy

• Price (UK): £450 (regular); ~£475 (long)
• Availability: Sea to Summit UK and major outdoor retailers
• Versions: Women’s Ascent -9C (regular/long); men’s Ascent available separately

8. Robens Serac 900 -20°C: warm and wallet-friendly

If you want deep‑winter warmth without deep pockets, the Robens Serac 900 is hard to ignore. In testing, The Great Outdoors praised its comfort and performance, noting that the high spec is almost “hidden under a price which is very good indeed.” It’s a serious, cold‑ready down bag that won’t shred your budget—a genuine contender for the best sleeping bag for winter camping if you don’t mind a little extra weight.

Why it’s great

The Serac 900 feels instantly cosy thanks to stretch seams on the upper-body baffles that let you move naturally while keeping insulation close, enhancing perceived warmth. Reviewers highlighted the well‑shaped hood and effective shoulder baffle, both easily adjusted from inside. It’s a simple, robust design that focuses on reliable warmth and comfort at a standout price.

Temperature and insulation

Robens packs in 900g of 600 fill‑power, RDS‑certified duck down (85/15) and controls it with stretch box baffles up top and standard box baffles elsewhere. A full zip baffle, adjustable hood and shoulder baffle seal in heat. The quoted ratings are impressively cold‑capable for UK winter use.

• Fill: 900g 600 FP 85/15 RDS duck down
• Ratings: Comfort -12°C; Limit -20°C; Extreme -43°C
• Baffles: Stretch box baffles (upper body) + box baffles; zip baffle; hood/shoulder baffle

Weight, pack size and fit

At 1,490g, the Serac 900 isn’t the lightest, and its compressed pack size is a chunky 26×23cm. But the warmth‑to‑price ratio is excellent, and the trim‑looking cut disguises generous, natural movement thanks to those stretch seams. Length is a roomy 220cm, suiting taller users.

• Weight: 1,490g
• Compressed size: ~26×23cm
• Length: 220cm (unisex)
• Fit notes: Looks trim but moves well; comfortable arm movement; cosy, effective hood

Standout features

• Stretch upper‑body baffles: Keep insulation close while allowing natural movement
• Thermal sealing: Adjustable hood and shoulder baffle; full zip draft tube
• Practical zip: ¾ two‑way main zip for venting and entry
• Easy adjustments: Differently shaped cords on the hood toggle for quick, no‑look tweaks
• Durable, greener fabrics: Recycled 20D 400T ripstop outer; recycled 20D 400T taffeta inner
• Ethical down: RDS‑certified fill at a budget‑friendly price point

Who it’s for

• Budget‑minded winter campers and bothy users who want serious cold‑weather performance without premium pricing.
• Backpackers who can carry 1.5kg in exchange for -12°C comfort and robust build.
• Taller sleepers who appreciate the 220cm length and forgiving, stretch‑assisted fit.

UK price and where to buy

• Price (UK): £351.99
• Spec: Unisex, one size (220cm)
• Availability: Commonly stocked by UK Robens retailers and specialist outdoor shops; check current size/stock locally.

9. Rab Solar Eco 4: synthetic security for wet UK winters

When the forecast screams sleet, spindrift and tent‑drip, synthetic fill is the safer bet. Rab’s Solar Eco 4 is a winter‑capable, recycled‑synthetic bag that holds warmth far better than down when damp, and it’s been picked by national testers as a “Best winter sleeping bag” for UK use. If your idea of the best sleeping bag for winter camping includes reliability in wet weather, this is it.

Why it’s great

The Solar Eco 4 is built for real British winters: a robust synthetic fill that still insulates when moisture creeps in, an honest sub‑zero rating, and a slightly wider cut that’s easier to live with in layers. It’s also kinder to the planet, using 100% recycled polyester insulation and fabrics, without pushing the price into premium territory.

Temperature and insulation

Rab uses its Stratus recycled synthetic insulation for dependable loft in the damp. The bag is rated to a comfort of -2°C and a limit of -8°C (extreme -27°C), putting it squarely in 4‑season territory for most UK hills—especially when paired with a warm mat and dry base layers.

• Fill: Stratus recycled synthetic insulation
• Ratings: Comfort -2°C; Limit -8°C; Extreme -27°C

Weight, pack size and fit

At 1.48kg, the Solar Eco 4 isn’t ultralight, but you’re buying wet‑weather security. It packs to roughly 45×24cm—bigger than an equivalent down bag—and fits sleepers up to about 6ft. The cut is a touch wider than many mummies, giving welcome wriggle room on long nights.

• Weight: 1.48kg
• Packed size: ~45×24cm
• Fit notes: Roomier mummy; comfortable for layered sleeping

Standout features

• Adjustable hood and collar: Snug down the top end to seal heat
• Zip baffle: Reduces heat loss along the main zip
• Handy zipped pocket: Stash a phone or headtorch where it stays warm
• Recycled build: 100% recycled fill and fabrics for lower impact

Who it’s for

• UK winter campers and bothy users who prioritise warmth‑when‑wet security.
• Ethical shoppers wanting recycled materials at a fair price.
• Newer winter backpackers who’d rather carry a little extra weight than risk damp down.
• Note: it’s warm—great from late autumn to early spring—but too much for midsummer.

UK price and where to buy

• Price (UK): £190
• Spec: Fits up to ~6ft; 1.48kg; recycled synthetic fill
• Availability: Commonly stocked by Rab and UK outdoor retailers; check current sizes and stock locally.

10. Western Mountaineering Kodiak MF: spacious, premium 0°F option

If you run cold, sleep on your side, or just hate the squeeze of tight mummies, the Western Mountaineering Kodiak MF is a luxurious winter refuge. Independent testers rate it “Best Overall” for combining wild warmth, real spaciousness and a stellar warmth‑to‑weight ratio. It’s a premium bag that feels like it’s radiating heat, yet still packs small enough for serious UK winter trips.

Why it’s great

The Kodiak MF’s party trick is comfort without compromise. With a cavernous 67in (170cm) shoulder girth, it suits side, stomach and back sleepers, and still seals heat thanks to massive 3D draft tubes and a well‑shaped, easy‑cinch hood. Despite the roomy cut, it remains light and compressible, so you’re not punished on the carry. Testers also note snag‑resistant zips and smooth, confidence‑inspiring build quality.

Temperature and insulation

Advertised to 0°F (‑17.8°C), the Kodiak stuffs in around 1.9lb (0.85kg) of high‑grade 850+ FP goose down. Continuous baffles let you shift insulation to fine‑tune warmth, and those oversized draft tubes cut off cold sneaks along the zip. Review teams slept comfortably at and a little below its rating, even pushing to about ‑10°F (with extra layers) when needed.

• Fill: 850+ FP goose down (approx. 0.85kg/1.88lb fill weight)
• Advertised rating: 0°F (‑17.8°C)
• Baffles: Continuous; large 3D draft tubes; efficient hood seal

Weight, pack size and fit

For the warmth and space on offer, the numbers are superb. The Kodiak MF weighed in at roughly 1.27kg (size regular) and compressed to an excellent 12.7 litres in testing—better than many tighter‑cut rivals. That 67in shoulder girth gives you real room to move and stash kit (water, batteries) inside; if you do feel a cool void, stuffing spare layers around you quickly solves it.

• Measured weight (regular): ~1.27kg (2.8lb)
• Measured packed volume: ~12.7L
• Girth (shoulder/hip): ~170cm/163cm (67in/64in) for the tested regular

Standout features

• Spacious cut, serious loft: Genuine room without sacrificing warmth
• Continuous baffles: Shift down where you want it as conditions change
• Big draft protection: Oversized zip draft tubes keep heat from leaking
• Snag‑resistant zip + choice of side: Smoother entry/exit, left or right zip
• Microlite XP shell (20D) with DWR: Wind‑resistant, water‑repellent face fabric
• Premium build: High‑quality stitching and hardware; made in the USA

Who it’s for

• Cold sleepers and restless side sleepers who want space and deep warmth.
• Backpackers who value comfort but still need a light, compact winter bag.
• UK winter campers targeting 0°C down to serious sub‑zero, with a good shelter and sensible moisture management.

UK price and where to buy

• List price (US): About $850 (premium tier)
• UK availability: Limited via specialist importers and independent outdoor retailers; pricing varies with stock and exchange rates.
• Sizes/zip: Regular/long options; choose left or right zip when ordering.

Final thoughts

The best sleeping bag for winter camping isn’t a single model; it’s the one that matches your route, your sleep habits and the weather you actually face. Use ISO comfort ratings as your baseline, treat -10°C comfort as genuine winter-ready for the UK, and pick down for maximum warmth-to-weight or synthetic for wet, stop–start forecasts. Whatever you choose, pair it with a high‑R mat, keep layers dry, and use vents and collars to manage moisture before it robs heat.

If you’re still deciding, start with your coldest likely night and work backwards on weight and budget. Our team can help you nail the right choice, with fast support, free delivery over £50 and a simple returns window. Ready to gear up for frosty pitches and bothy nights? Explore curated winter kits at take a hike uk.