NeoAir XTherm NXT Large Sleeping Mat

599g (excluding bag)
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UOG TOP PICK - NeoAir XTherm NXT: It’s low weight, incredibly hight R-value, and durable materials, set this mat apart from its competitors, its “the best warmth-to-weight ratio of any sleeping pad ever creat…

RRP: $580.70
| You save: $85.68 (14%)
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UOG TOP PICK - NeoAir XTherm NXT: It’s low weight, incredibly hight R-value, and durable materials, set this mat apart from its competitors, its “the best warmth-to-weight ratio of any sleeping pad ever created” so, it has to be one of our top pics!

Thermarest says: 

With cutting edge Triangular Core Matrix™ construction and ThermaCapture™ technology, the XTherm NXT delivers a 7.3 R-value while weighing just 15.5 oz (439 g) in the Regular size. Put another way, the best warmth-to-weight ratio of any sleeping pad ever created. It is warmer, lighter and thicker than the previous model, which is why the XTherm NXT cements the legacy of being the go-to sleeping pad for alpinists, mountaineers and extreme cold expeditions. At 3-inches thick, with horizontal baffles, all-night comfort and support are at hand, while 70D nylon on the bottom ensures the XTherm NXT holds up to extended expedition use. The WingLock™ Valve allows for rapid inflation and deflation but is also intuitive and easy to use in frigid weather when the gloves are not coming off. If reliable overnight warmth is the demand no matter how far the mercury dips and space in the pack is at a premium, there’s no finer sleeping pad than the XTherm NXT.

Our Verdict

This mat is the traditional body-mapped shape, though a larger rectangular mat is available.  I'm a side sleeper and felt very comfortable and well-supported; it’s 7.63 cm thick, so you are well off the ground and well insulated.

Therm-a-rest have been listening to hikers feedback and have made this mat much, much quieter than in past seasons. It’s a much nicer mat to sleep on, and you won’t irritate your camp mates tossing and turning during the night.

The mat comes with its own pump sack; it took me eight pumps of the sack to fully inflate the mat.

The mat has an incredibly hight R-value of 7.3, this is a mat that can be used in arctic conditions, and weighs only 599 grams, truly impressive.

- Reviewed by Ultralight Outdoor Gear

In-depth Reviews:


  • Best Warmth-to-Weight Ratio Ever: Refined Triangular Core Matrix construction and ThermaCapture technology deliver a cold-conquering 7. R-Value while cutting over 2 oz (57 g) in weight from the previous model.  
  • Premium Comfort: A 3-inch (7.6 cm) thick profile and horizontal baffled structure delivers premium backcountry comfort while keeping the weight to a minimum.
  • Ultralight Durability: 70D nylon on the bottom withstands the wear and tear of extended expedition use, while 30D ripstop nylon on top keeps it light and packable.
  • WingLock™ Valve: Delivers fast one-way inflation and rapid deflation without giving up the ability to easily purge air while you lay on it for comfort micro-adjustments—even with gloves on.
  • Pump sack, stuff sack and field repair kit included.


  • Weight: 599g
  • Dimensions: 64 x 196 cm (25 x 77 in)
  • Thickness: 7.62 cm (3 in)
  • R-Value: 7.3

ASTM R-Value:

From 2020, there is a new industry standard for measuring the R-value (level of insulation) of sleeping mats – ASTM F3340-18. This new standard is the sleeping mat equivalent to the EN rating for sleeping bags.

You can now directly compare the R-value of mats rated using the ASTM F3340-18 with confidence that is a fair and accurate comparison between mats. In simple terms, the higher the R-value, the warmer the mat.

In general terms, an R-value below 2.0 is for summer use, 2.0 to 4.0 is for cooler 3 season use and 4.0+ is for winter temperatures. This will be also be dependent on your sleeping bag, how cold you sleep etc. Please contact our customer service team if you need advice on choosing the right mat for your activity.

Material & Construction

  • 30D Nylon Ripstop Top
  • 70D Nylon Bottom

Help & advice:

Thermarest NeoAir XTherm NXT Large Sleeping Mat

NeoAir XTherm NXT Large Sleeping Mat

RRP: $580.70
| You save: $85.68 (14%)

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