Best sleeping bags for 2025 | Tested and reviewed for all seasons

When he reviewed a load of three-season sleeping bags in May 2025, gear tester Matt Jones decided that this was the best. It’s ultralight, very cosy and well-designed.

It's the lightest of all of the bags he tested, weighing just 690g/1lb 8oz in the regular size. It compresses to 25x16cm in its bag, which outperforms most competitors.

The Xenith III has a very good warmth to weight ratio. It's made with luxury 900-fill power down, plus a superlight 10D Plasma shell fabric – this means it's super cosy, but also very light.

Unlike most three-season bags, you get vertical chest baffles and slanted main body baffles, which maximise heat retention.

It offers superior comfort compared to most ultralight options. Features include a full-length zip, a multi-panel footbox and hood, and an integrated draught collar. The mummy-style design provides a snug fit without feeling restrictive.

With EN/ISO temperature ratings of -2°C (comfort) and -8°C (limit), the Xenith III is a standout choice for UK hill and mountain use from early spring to late autumn. The only drawback is it's high cost, but Matt reckons it's worth it.

Read our Mountain Equipment Xenith III review here.

We'll state the con of this sleeping bag straight away: at 1,450g and packing away into a 46 x 24cm package (long size), this isn't a compact sleeping bag. But everything else about it is fantastic. It's comfortable, warm, durable, and sustainable.

The Orbit 0° is made from a 50D recycled polyester shell and 75D microfibre lining, with Hollowfibre synthetic insulation. Not only are these materials tough, but they're also much softer and nicer to touch than the slippery, shiny feel you often get.

Its Hollowfibre synthetic insulation means the Orbit 0° gives down sleeping bags a hiding on price but is also effective at insulating in damp conditions. There are other features to help improve insulation too, such as a draft collar, adjustable hood, and efficient mummy shape. The Orbit 0° is compatible with zip coupling too.

There are two lengths available, plus a women's version (suitable for up to 175cm height). Sustainability is very good too. The Orbit 0° is PFC-free and uses a recycled shell fabric. Deuter is also Fair Wear Foundation member with 'Leader' status.

Find the women's version here.

It's easy to be fooled by this lightweight sleeping bag that appears to be filled with not very much insulation. Such is the deceptive beauty of high-quality down.

The Ultra 0° uses high loft 850-fill goose down, which means you don't need much to get a warm sleeping bag. Thus, 295g of fill (long size) gives the Ultra 0° a temperature rating suitable down to about 2°C. For a 600g (long size) sleeping bag, that's very impressive.

There's another big plus point to the Ultra 0°. While most sleeping bags come in regular and long sizes, the Ultra 0° comes in five sizes: small, medium, wide medium, large, and wide large.

Furthermore, you get a very sustainable sleeping bag here too. Naturally, the down is responsibly sourced, but the Exped Ultra 0° goes further. The Pertex Quantum outer material is recycled, as is the zip. It is a bluesign-approved product and PFC-free; Exped has even offset the manufacturing and shipping emissions.

Downsides to this sleeping bag include the trade-off with the 10D Pertex fabric. Sure, it's super lightweight and has the potential to be long-lasting, but you need to be very careful with it to achieve that. It's a tad delicate. It's also understandable to baulk at the price on initial inspection. However, you do get a lot in return.

Read our full Exped Ultra 0 review.

We're big fans of Rab's versatile Neutrino range. With 10 total products sporting various weights and materials, the 400 is a stand-out contender. Rab haven't skipped a single detail; each bag is hand-stuffed and fully-featured, treated with a level of care that has earned the Neutrino 400 a number of top awards from us over the past few years.

Features include an adjustable hood, ¾-length YKK zipper, angled footbox, internal stash pocket, cotton storage sack and waterproof compression sack, amongst others. As well as being packed with nifty features, the Neutrino 400 has a unique baffle design that solidifies its place at the top of this list.

Baffles are the individual pockets of down fill responsible for the bag's insulation. While most bags go for horizontal baffles, the chevron-style arrangement in the Neutrino 400 allows for more loft, fewer cold spots, and uses less overall material.

We're also very pleased to see some newly implemented sustainability upgrades. Rab have used PFC-free DWR treatments as well as increasing the amount of recycled materials in their construction, particularly in the Pertex Quantum shell.

Read our full Rab Neutrino 400 review or find the women's version here.

The Big Agnes Fly Creek UL 25 is a premium, ultralight three-season sleeping bag. 

It offers impressive warmth for its weight. The regular size is just 700g and packs down to a compact 24cm x 20cm, yet it's rated to +2°C comfort.

The Fly Creek has a slim tapered shape, with high-quality 850-power down and diamond quilting. It should be noted that the slim fit may feel restrictive for broader builds.

Unsurprisingly for an ultralight bag, features are minimal. There's a snug hood, ergonomic footbox, draught collar, and a small half zip. The zip is effective but fiddly; the fact it's only goes half the way down limits ventilation. 

It's wonderfully sustainable, though. The Fly Creek uses NetPlus fabric made from recycled fishing nets, a PFAS-free DWR, and bluesign-approved, RDS-certified down fill.

While this bag is excellent for ultralight camping, it may not suit those who prioritise comfort or versatility in varied weather conditions. It's competitively priced for a premium bag, but it's certainly not cheap (£450 RRP).  

Read our full Big Agnes Fly Creek UL25 review.

Rab has pedigree in sleeping bags, which is on display here. There are some great features including YKK zips and an adjustable hood, while there's a weatherproof Pertex Quantum outer shell.

The down insulation has a fill power of 650, which isn't all that high, but it's pretty warm. It comes with a hydrophobic treatment from Nikwax to help protect performance in damp conditions.

Rab has given this sleeping bag a 'sleep limit' of -16°C. We've not tested it down to that temperature, but we can say we'd be comfortable sleeping in this bag in single-digit minus temperatures.

The pack size is pretty compact and a weight of 1,351g is very good, so it competes well with the best winter sleeping bags.

For more info, read our Rab Alpine 800 Down review.

The Mammut Comfort Down -5C is particularly useful for those who sleep on their side. It has a relaxed mummy shape and a distinctive centre zip, enabling excellent ventilation and ease of access.

It comes in two lengths, with a -5°C lower limit for the men’s/L size and -7°C for the shorter women’s/M size. It performs well in terms of warmth to weight and packability, though it can’t compete with higher-spec bags. 

It's pretty sustainable, with with 600g of 100% recycled 650 fill power duck down and recycled polyester fabrics, though there's no responsible sourcing certification. There's no hydrophobic treatment, which might make it less durable in the long run.

It's generously-sized, so smaller users might find that there's too much dead space inside – this reduces thermal efficiency. But for Matt on test, it proved to be comfortable and warm.

The Mammut Comfort Down is certainly versatile, thanks to The central zipper, dual drawcord hood, and 'blanket mode'. But Matt finds that it's not as 'premium' as other Mammut models, as there's no internal pocket or noise-reducing hood lining.

Overall, the Mammut Comfort Down -5 is a comfortable and versatile bag with a practical centre zip – we'd say it's a great all-rounder.

Read our Mammut Comfort Down review here.

The price is one of the biggest positives with this winter OEX sleeping bag, as you can get it for as low as £169. That's great value for a sleeping bag that has a comfort temperature rating of -9°C and a comfort limit of -16°C. While we're not sure the bag is quite up to those limits, it's certainly good for camping just below zero.

There's 900g of 600 fill power hydrophobic down, which feels about right for this price. You'll find better insulation in some of the other picks here, though.

Features include a decent neck collar baffle and a good hood, while a weight of 1,399g is pretty damn good. It packs down well, too.

The overall build quality was reflective of the price and the sleeping bag doesn't feel quite as premium as other options here.

See our full OEX Leviathan EV 900 Down Sleeping Bag review for more.

The Marmot Trestles Elite Eco sleep bags have consistently impressed us with their combination of high performance and reasonably sustainabile materials.

The Trestles Elite Eco 30 is our pick of the bunch because it has a temperature rating of around zero, which makes it useful for most scenarios. It's made from fully recycled materials throughout, including the innovative HL-ElixR Eco insulation. For a synthetic sleeping bag it offers an very good warmth-to-weight ratio and maintain insulation even when damp—a hallmark of synthetic materials.

The Trestles Elite Eco 30 is also compact, certainly for a synthtic sleeping bag. It has a full-length main side zip that resists snagging and an additional zip on the opposite side for improved ventilation and ease of access.

Inside the bag, you'll get plenty of space for a hiking sleeping bag, especially in the foot area, setting it apart from traditional mummy-shaped designs. The hood cinches snugly around the head, enhancing comfort during colder nights.

While there are some minor points to consider, such as the main side zip not extending fully to the foot, resulting in warmer feet even when partially open, and the shoulder baffle being slightly less effective compared to some competitors, these are relatively minor concerns rather than significant drawbacks.

Overall, the Marmot Trestles Elite Eco stands out as a top choice for those seeking both performance and eco-conscious design in a synthetic sleep bag.

We're quite fortunate at Live for the Outdoors to have a primary school-aged tester who's prepared to climb mountains, sleep in strange places, and generally give outdoor kit the thrashing it deserves on a regular basis. We should also point out he doesn't actually work here but is closely related to someone who does.

He graduated to his first 'proper' sleeping bag when he turned 6 years old, and the Snugpak Explorer has been an excellent choice. At 170cm long (he's about 130cm tall), it's nice and roomy with plenty of space to grow into, and the thing we really like is it's manufactured to the same standards as Snugpak's adult sleeping bags.

The Explorer has the same technical insulation and fabrics, including a Supersoft lining and technical Isofibre insulation. Like most sleeping bags you can fully unzip it to use as a duvet, plus you can unzip just the area around your feet to make it into one big airy tunnel.

Available in a range of three colours, including blue and purple, but the camouflage one has gone down very well with our mini reviewer. The price is very fair for what you're getting here too – basically an excellent sleeping bag for camping with kids from spring through summer.