Helly Hansen Odin Everdown hooded jacket review: game-changing warmth-to-weight

Helly Hansen Odin Everdown hooded jacket: first impressions

As a journalist in the outdoor industry, I’m constantly testing products that promise to change the game. And as much as this is a dream job, it has had the rather unfortunate effect of turning me into a bit of a sceptic, because so very few products tend to deliver on these claims. Occasionally, however, something properly novel comes down the pipeline that blows me away – as was the case with the phenomenal Zenbivy Ultralight Bed last year. And now, to kick off 2025, Helly Hansen have managed to do it with the Odin Everdown jacket.

In a nutshell, the Helly Hansen Odin Everdown down jacket is a warm outer layer for chilly mountaineering, backpacking or wild camping trips. Which, in itself, is nothing revelatory – that’s what a down jacket’s supposed to be. Where the Odin Everdown properly breaks the mold is in delivering heavyweight warmth in a package that’s literally as light as a sheet of feathers.

Seriously, in medium, this weighs a jaw-dropping 313g. To put that in perspective, that’s lighter than a single can of Coke – or less than half the weight of the similarly warm Mountain Equipment Lightline (which comes in at 790g). This is thanks to Helly Hansen’s use of THINDOWN, an insulator that combines the utility of synthetic insulation with the weight and packability of down. Pitched as “the world’s first real down fabric”, THINDOWN is more akin to polyester insulation than it is to down feathers, comprising 100% stitched down that’s molded into panels. The result is a natural insulator that’s twice as warm as loose down and four times warmer than polyester – allowing Helly Hansen to make a jacket that’s incredibly light and packable for its warmth – and winning the brand a coveted ISPO Award in 2023.

All of this game-changing tech does come at a cost, though. The Helly Hansen Odin Everdown jacket will set you back a hefty £400 when bought directly from Helly Hansen. This is £75 more than the RRP of a Rab Neutrino Pro and £140 more than the RRP of the aforementioned Mountain Equipment Lightline – two jackets that, in my experience, offer a comparable level of warmth.

If you’re looking for something with an equivalent weight, your main option is going to be something like the Ghost Whisperer 2 from Mountain Hardwear, which has an RRP of around £300 and weighs a teeny tiny 246g. In my experience, though, Mountain Hardwear’s prized design doesn’t even come close to delivering comparable levels of warmth to the Everdown, with the Ghost Whisperer being more of a spring/summer/fall layer compared to the Everdown’s ability to keep you warm in temperatures well below zero. All of this hopefully illuminates why I think this jacket is actually well priced for what it delivers, which is something I never thought I’d write about a £400 coat.

Helly Hansen Odin Everdown hooded jacket: in the wild

I was lucky enough to get my hands on a sample of Helly Hansen’s Odin Everdown jacket back at the start of November 2024. It arrived just in time for some seriously cold weather, which meant I could properly put the warmth claims of this coat to the test. In total, I used it on an untold number of cold winter walks around my home near the Chiltern Hills in England; on a skiing trip in the Alps where it became my go-to jacket for practically everything; for a deep winter wild camp on Dartmoor in south-west England where the temperature dropped down to around 21°F (-6°C) Celsius; and for keeping me toasty warm on a few wanders in Bannau Brycheiniog (the Brecon Beacons) in Wales – including a hike up Pen y Fan in rare snowy conditions. And all in, it left me nothing but impressed.

Helly Hansen Odin Everdown hooded jacket: fit and features

The first thing I really appreciated about the Helly Hansen Odin Everdown jacket was the fit. It’s tight enough to lock in warmth, yet baggy enough that you can comfortably layer up underneath. It’s also comfortable under both a pack or a hardshell, with no surplus toggles, zips or pockets that dig into you while you walk. For added warmth, the back of the jacket comes down a little to fully cover your waist and to provide some extra protection to the tops of your butt cheeks. What’s more, the cut of the wrist cuffs is such that the internal down panelling drops down a little over your hands which, in my opinion, makes the coat noticeably warmer around the wrists.

When it comes to features, though, I was initially underwhelmed with the Odin Everdown’s offerings. It comes with two hip pockets, one central zip, a hood, a RECCO reflector and a stuff pouch. And that’s it. There are no zippers on the pockets and there’s no internal stuff pocket. There aren’t even toggles on the hood to tighten it down in high winds, nor are there cuffs on the wrists. It’s the most simplistic jacket I’ve ever come across, which I came to appreciate the more I wore it – even if I was a little surprised at first.

You see, Helly Hansen have worked to create the lightest, warmest jacket out there; a layer that delivers more warmth per gram than any other on the market. And even though I’ve not tested every down jacket available today, I’ve yet to come across something that even comes close. And you know what? I never zip up pockets or use those stuff pockets anyway.

Meet the reviewer

Craig Taylor

Growing up just south of the glorious Brecon Beacons National Park, Craig spent his childhood walking uphill. As he got older, the hills got bigger, and his passion for spending quality time in the great outdoors only grew – falling in love with wild camping, long-distance hiking, bikepacking and fastpacking.

Helly Hansen Odin Everdown hooded jacket: THINDOWN

While we’re on the subject of features, it’s worth doing a deep dive into the biggest ‘feature’ of this coat: the THINDOWN insulation that makes it what it is.

This is a layer of RDS-certified goose down that’s touted as “the world’s first real down fabric”. Coming in rolls, the insulation is more akin to polyester than standard down feathers, an invention which has allowed Helly Hansen to make a down jacket that’s completely void of baffles. This pretty much eradicates any and all wind from entering your jacket and cooling you down, allowing the Odin Everdown to work well as a windbreaker as well as an insulating layer.

What’s more, thanks to the panel-like insulation, Helly Hansen have been able to evenly disperse the down throughout the coat, which eradicates cold spots and ensures more consistent insulation. In my experience, this has the added benefit of the jacket warming up immediately, practically at the point you first put it on (unlike in conventional down jackets where it can take a while for the feathers to catch your body heat and warm up).

Helly Hansen Odin Everdown hooded jacket: warmth, weight and packability

All of which makes the Odin Everdown just as warm as any classic belay jacket you might use on a wild camp. For comparison's sake, I actually headed out on a hike in temperatures hovering around 27°F (-3°C) wearing just the Odin Everdown over a thin Icebreaker Merino base layer and I felt perfectly comfortable the whole time.

Around halfway I then swapped jackets and peeled on my Mountain Equipment Lightline – a beloved coat among winter wild campers and backpackers that’s about twice the size and weight of the Everdown. And, again, I was comfortable – not warmer, not sweatier: I was just as warm and comfortable as I was in the Everdown, despite the Lightline being more than twice as big and twice as heavy.

Now, granted, this wasn’t exactly a scientific analysis, but my experience with the Everdown over the last three months has given me just as much confidence in its ability to keep me warm as I’ve built up in the Mountain Equipment Lightline over the years. So much so, in fact, that I can’t think of a reason I’d ever opt for the heavier Lightline again, with the Odin Everdown now poised to become my go-to warm layer on winter wild camping and backpacking trips from here on.

When it comes to packability, this is another way in which the Odin Everdown really stands out from the crowd. In medium, this jacket packs down smaller than a Patagonia Nano Puff, a three-season stand-out mid layer that’s long been praised for its size and weight. When fully compressed, the Odin gets down to about the size of a mango, which is jaw-dropping for a coat that delivers as much warmth as it does.

To sweeten the deal even more, it also weighs a barely noticeable 313g. At this weight, it’s kinda pointless opting for anything else – even if you’re heading out on a hike in warmer conditions where you probably won’t need anything this warm. Hell, at 313g, you could also incorporate the Everdown into your fastpacking or bikepacking setup, which (to me), makes it one of the most versatile warm layers available.

Helly Hansen Odin Everdown hooded jacket: waterproofing

As is the case with most jackets in this category, the Everdown is not waterproof. The nylon outer is reasonably water repellent to the odd droplet, but I found it quickly wets out in any real rain. Therefore, if you’re heading into wet environments, it’s crucial that you pair this with a shell or keep it in your pack until the weather dries out.

Helly Hansen Odin Everdown hooded jacket: durability

For a jacket this light and packable, I found the Odin Everdown to be reasonably durable. Featuring a 10-denier ripstop Nylon outer shell, it’s tough enough for day-to-day use and for wear in the mountains, although you wouldn’t want to wear it while bushwhacking. A rogue thorn or a misplaced bit of barbed wire will easily put a hole in the Odin Everdown, so consider pairing it with a hardshell if you’re walking through dense woodland or wearing it anywhere it could get snagged. Unlike regular down jackets, though, the Helly Hansen Odin Everdown comes with THINDOWN panelling, so feathers won’t spew out of this coat should you rip it. Much like with polyester insulation, the jacket is still perfectly capable of keeping you warm even if a small hole develops (although I, thankfully, haven’t been able to test this claim, yet).

In a nutshell, I love the Helly Hansen Odin Everdown. It’s the lightest and most packable down jacket I’ve ever come across, delivering levels of warmth that rival coats twice its size. It promises next-level warmth to weight, and in my experience, it delivers exactly that. Honestly, I think this is the new benchmark when it comes to warm winter down jackets for backpacking, mountaineering and wild camping. And because it ticks so many boxes I fully expect the Everdown to become the only jacket I ever pack from here on out whenever it’s set to get a little chilly – whether I’m going fastpacking or bikepacking in milder spring temperatures or heading out on a deep winter wild camp. Granted, at $450/£400 this coat isn’t cheap, but for the amount of use you’ll be able to get out of it, I think it’s a worthy investment if you can comfortably afford it.

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