Exped MegaMat reviewed

The Exped MegaMat is a 10cm self-inflating foam mattress for one person, and in the LXW size that Exped UK sells it measures 197 x 77cm, wider than most camping mats by more than 10cm. It costs £290, weighs 2.6kg and carries an R-value of 8.1, which makes it a mattress for car camping, campervans and the spare room rather than for a rucksack.

Construction and comfort

Inside is open-cell polyurethane foam at 16 kg/m³, cut with horizontal air channels that reduce weight and help it pack down. Exped calls the feel soft and pressure-relieving and pitches it at back and side sleepers alike. Exped says 10cm of foam is enough to stop most campers bottoming out, and vertical side walls hold that depth right to the edge, so you are not perched on a tapering crown. The top fabric is recycled four-way stretch polyester tricot, quiet and soft against bare skin, and the base is a tougher recycled 75D polyester with a TPU laminate. Firmness is yours to set: top it up with the supplied pump for more support, or press the one-way flap in the inflate valve to let a little air out.

What R 8.1 means in practice

An R-value tells you how much a mat resists the flow of heat from your body into the ground. Under the camping-mattress test standard ASTM F3340, it is measured between a heated plate and a cold plate under constant pressure, so a higher figure is a warmer mat and figures can be compared across brands. Exped quotes 8.1 on its UK product page with a temperature guide of -40°C. For UK camping that covers every season, including frosty nights at a winter basecamp.

How it compares with other deep singles

The MegaMat’s obvious rivals are other deep foam singles. Here is how it lines up against the NEMO Roamer and the Therm-a-Rest MondoKing 3D in their standard sizes, at UK prices at the time of writing (October 2026).

The MegaMat is the widest and the warmest of the three, and also the bulkiest roll and the dearest. The Roamer packs to less than half the length, which matters in a small car boot, and the MondoKing is the cheapest way into a deep mat. If you want the MegaMat’s width elsewhere, the MondoKing XXL and the Roamer Single Wide both reach 76cm.

Setting up, packing and care

On the first outing Exped asks you to let the mat self-inflate for an hour, pump it full, then leave it for 24 hours in a warm room so the foam recovers. After that, opening the valve at camp does most of the work. It rolls to 79 x 25cm, about the length of a rolled sleeping bag, and goes into Exped’s Sidewinder bag with a repair kit and the Top Up Pump. Clean it by hand with warm water and a mild detergent, and store it flat with both valves open so the foam is ready to expand next time.

Exped UK covers it with a five-year warranty and repairs punctures free within that period, postage aside. Exped’s UK shop only sells the LXW. The narrower MW and LW versions at 65cm appear in Exped’s specification but you would have to find them through another dealer.

Buy the MegaMat if you sleep wide, sleep on your side or camp into the colder months, and your mattress travels no further than the car. Couples should look at the MegaMat Duo, and anyone counting grams needs an air pad instead.