Sea to Summit Ultralight Insulated Sleeping Pad: Reasons to Love it

A sleeping pad can make or break your camping experience. For years, I was using cheap sleeping roll mats (like a Yoga mat), but these offered no warmth and little cushioning. Before my Patagonia adventure in 2024, I was in dire need of a quality inflatable sleeping pad for my tent. The most popular brand by far is Therm-a-rest; however, these come at a premium price point. So I searched for a better value inflatable sleeping pad which was lightweight, compact and had 2/3 season compatibility. That’s when I found the Sea to Summit Ultralight Insulated Sleeping Pad, which ticked all my criteria and was within budget. This kit review will give the technical specs, strengths and weaknesses of the sleeping pad as well as some alternatives and a kit rating.

Sea to Summit Ultralight Insulated Sleeping Pad – Kit Review

Overview

The Sea to Summit Ultralight Insulated Sleeping Mat is designed for backpackers, trekkers, bikepackers, and minimalist campers who need a small, packable, lightweight sleeping pad. The insulated version adds warmth for use in the shoulder seasons. The Ultralight Insulated Sleeping pad uses Air Sprung Cell™ technology to improve stability and comfort whilst minimising weight and excess material. As the baffles form a matrix, they can adjust to the body’s shape more easily than vertical or horizontal baffles. Sea to Summit has focused on durability for this lightweight sleeping mat, using extruded TPU Lamination to reduce delamination and high-quality welds for robustness. The combination of Thermolite® and Exkin Platinum® insulation gives an R-Value of 3.1, which is ideal for 3 seasons (spring the fall). There is a Women’s specific version which has a wider shape at the hips and narrower at the shoulders.

Tech Specs

• Weight: 480g (reg)
• Performance: 2.5 Season
• Thickness: 5cm / 2in
• R-Value: 3.1 ((ASTM F3340-18) – suitable for 3-season use)
• Packed Size: 12.5 x 24 cm
• Best Use: Lightweight Backpacking
• Price: £140 / $159

Key Features

• 3.1 R-Value is effective for 2.5-3 season camping (late spring to early fall).
• Exkin Platinum® insulation reflects your radiant heat to you, while Thermolite® insulation prevents convective heat loss.
• Lighter, quieter and durable 30D/40D face fabric, along with Sea to Summit’s liquid-extruded TPU lamination, is extremely reliable and durable.
• Quick and easy inflation, deflation and adjustment thanks to the genius multi-function valve with a high-flow one-way valve setting.
• Anti-microbial treatment added to the TPU lamination formula prevents internal mould growth inside.
• PillowLock system prevents your Sea to Summit Aeros Pillow from slipping.
• Airstream Pump Sack uses a clever integrated design to pump air into the sleeping pad, store the pad when rolled up and includes a repair kit (plus spare valve insert). The Airstream Pump can be used on the Aeros Pillows, too, when turned inside out.

My Experience

I bought the Sea to Summit Ultralight Insulate Sleeping Pad at a discounted price of £82, down from the £140 RRP. For this bargain price within my budget, I was excited to test out the new camping addition. My first impression was how light and compact the sleeping pad was when I unboxed it! It truly lives up to the ultralight name in a Regular size and helps when packing inside my Osprey Atmos Backpack. When using it on camping in the UK, trekking in Patagonia or backpacking in British Columbia, I’ve been impressed by the R3.1 warmth provided and protection from the ground.

Despite only being 5cm in height, I don’t tend to bottom out much unless I am pushing weight on one point. I tend to notice the noise of the baffles (Air Sprung Cells) when I move around, but it’s a comfortable sleeping pad for sure. One feature I really appreciate is the integrated AirStream pump stuff sack, as it removes the need for another part to carry. Sea to Summit’s multifunctional valve is very effective at quickly inflating and deflating the sleeping pad. So far, I have never had a puncture or any durability concerns on any of my many nights away camping. This sleeping pad has become an essential part of the Camping Packing List.

Sea to Summit Ultralight Insulated Sleeping Pad Strengths

• Excellent Weight-to-Warmth Ratio – At under 500 g for the Regular size, this sleeping pad is definitely lightweight. It’s warm enough for spring to autumn camping with an R-value of 3.1, thanks to its Exkin Platinum® and Thermolite® insulations.
• Compact Packed Size – Packs down to a small cylinder, easily rolls and stashes in a side pocket of a backpack and inside the AirStream Stuff Sack for quick packing.
• Comfortable for an Ultralight Pad – Air Sprung Cell™ design feels more stable and less “bouncy” than standard horizontal baffles.
• Quick Inflation & Deflation – The multi-function valve with the Airstream Pump Sack makes inflation fast and avoids moisture buildup inside the pad, along with the anti-bacterial treatment.
• Durable for Weight Class – The 30D/40D nylon construction is abrasion-resistant enough for careful backcountry use. The baffles get a little dirty, but they feel robust even when leaned on.
• Great Value – A subjective one, as it depends on your budget, but the Ultralight Insulated Pad gives a sub 500g weight, an R Value of over 3 and great comfort for under £150. This combination makes it very competitive in the mid-range category. If you have more money, then consider the Therm-a-rest and Nemo alternatives below.

Sea to Summit Ultralight Insulated Sleeping Pad Weaknesses

• Narrower Than Some Alternatives – 55 cm width may feel tight for side sleepers or restless movers. I haven’t experienced this too much as a side sleeper, but you have to be careful when rolling over. If the pad were larger, then it likely wouldn’t be lightweight, or it would be more expensive.
• Not Ideal for Winter – R-value of 3.1 is insufficient for cold-weather or winter camping without extra insulation. A combination of a 3-season sleeping bag (Rab Alpine 800 Down Sleeping Bag) and a sleeping bag liner with some base layers can help you push to lower temperatures.
• Slight Noise – Not as loud as some ultralight pads, but still has a crinkly sound when moving.

Best Alternatives

1. Therm-a-Rest NeoAir XLite NXT – Slightly warmer (R-value 4.5), lighter in some sizes, but more expensive and noisier.
2. NEMO Tensor Insulated – Quieter fabric, slightly thicker (7.5 cm) for more plush comfort, similar weight but higher price tag.
3. Big Agnes Zoom UL Insulated – Warmth similar to the Sea to Summit, larger baffles for comfort, but bulkier when packed.
4. Klymit Static V Lite Insulated – Heavier but much more budget-friendly, with a unique V-baffle design.
5. Rab Stratosphere – A 3-season sleeping pad with a warmer 3.8 R Value and height of over 8cm. This sleeping pad is a great budget option, but it does weigh nearly 1kg with stuff sacks and pumps.

Sea to Summit Ultralight Insulated Sleeping Pad Kit Rating

Sea to Summit Ultralight Insulated Sleeping Pad: Final Thoughts

A superb choice for ultralight backpackers who need a balance of warmth, comfort, and packability for 3-season trips. Loses points for the narrow width in the Regular size and the noisy baffles, but overall, it’s a highly dependable pad for lightweight adventures. I would highly recommend the Sea to Summit Ultralight Insulated Sleeping Pad for any campers needing a lightweight, durable and compact sleeping pad.