Budget camping mattresses used to fall into two unsatisfying camps: thin foam roll mats that do little to cushion you from hard, uneven ground, and bulky flocked airbeds that are prone to punctures and require either a pump or superhuman lung capacity to inflate.
The self-inflating mat felt revolutionary when it first appeared. I remember my boyfriend giving me a Therm-a-Rest in the mid-2000s and promptly declaring myself a camping convert. But for ageing side-sleepers like me, these foam- and air-filled mats have their limits: unless you opt for one at least 8cm thick, rocky ground and aching hips can still detract from the magic of a night spent outdoors. And as mats get thicker, they also tend to get heavier, bulkier and more expensive.
More recently, lightweight inflatable sleeping pads have become the go-to option for backpackers and mountaineers. These use air-baffled chambers – small to medium-sized pockets of air – to offer much of the comfort and bounce of an airbed, but in a tougher, far more compact package that rolls down to the size of a small water bottle in many cases. The downside is price, with comfortable, premium brand trekking airpads often costing upwards of £75.
Which is why the idea of a lightweight sleeping pad for under £50 sounds almost too good to be true. Enter the Simond MT500 trekking mattress from Decathlon, which comes in at £44.99 for the standard (L) version, or £49.99 for the XL. The MT500 range attracts glowing user reviews, with buyers praising its comfort, compact pack size, low weight and value for money.
I previously tested the insulated three-season version of the MT500 and named it the Filter’s best budget camping mattress of 2025. So, when the opportunity came to try its stripped-back, cheaper summer sibling, I was keen to see whether it offered the same blend of value and performance – especially since many people only camp in warmer months, when extra insulation may be unnecessary.
View at Decathlon***
How I tested
One of my few grumbles about the standard MT500 L is its narrow shape. That may be a sensible compromise for campers counting grams and litres, but is less appealing for taller or broader sleepers, or anyone (like me) who likes room to sprawl. So, I chose to test the Simond MT500 XL instead. At 195cm by 60cm, it adds 15cm of length and 8cm of width for a modest £5 extra.
I repeated the tests I previously developed for assessing camping mattresses, scoring it for comfort, durability, packability, and ease of inflation and deflation.
To test comfort, I placed the mattress on a hard wooden floor over several sharp stones and lay on it in a sleeping bag on my back and my side, rolling between positions to see if I could feel the stones beneath me, detect any pressure points around the hips or shoulders, or whether I slithered off the mat and on to the ground.
Durability was assessed by jumping lightly on it with bare feet, dropping on to it from standing height, scraping at it with a pointed stone, and spraying the underside with water to see how readily moisture penetrated.
Finally, I spent a late-April night under canvas in my back garden for the ultimate test: would it stay inflated, warm and water-resistant enough to keep me comfortable until morning?
The mattress tested for this review will be donated to the People’s Republic of Stokes Croft, which supports people sleeping rough in Bristol.
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What you need to know: from price to comfort
View at DecathlonThe Simond MT500 XL costs £49.99, undercutting many rival inflatable sleeping pads by a considerable margin, while offering dimensions that will appeal to taller campers and anyone who values a little extra wriggle room. The pad tapers at the head and lower legs, presumably to reduce weight and pack size, so these dimensions only cover the shoulders and hips – but this is precisely where that extra width matters.
Its internal air chambers run lengthways, providing 5cm of cushioning between you and the ground – more than a foam mat or many budget self-inflating mats – while packing down much smaller and weighing far less than a traditional single airbed. Rolled up, it takes up about the same space as a 1-litre water bottle. For summer campers, festivalgoers and backpackers, that combination of low weight, compact size and relatively cheap price is likely to be the biggest draw.
The mattress has an R value of 1.5, referring to how well it resists heat transfer from your body down to the ground. As a rule of thumb, ratings of 1 to 2 are usually sufficient for summer camping, when overnight temperatures stay above about 8C. Colder temperatures require a higher R value, so this is primarily a mat for warm weather, rather than year-round adventures. Those camping in colder months would be better served by the Simond MT500’s three-season sibling, which confusingly has the same name – but is orange rather than blue-green, and costs £69.99 for the XL model (or £64.99 for the standard L version).
Minor tears can be fixed with a self-adhesive repair patch, and Decathlon offers its standard two-year warranty against defective materials or workmanship.
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Specifications
Weight: 600g
Dimensions (packed): 28cm x 10.5cm
Dimensions (inflated): 195 x 60 x 5cm (LWH)
R value: 1.5
Self-inflating: no
Pump included: no – inflatable by mouth
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What we love
It took less than a minute to inflate and is very comfortable. The lengthways air chambers – rather than the cross-hatched layouts or other configurations used in some rival mats I tested – seemed to absorb the pressure from small rocks and uneven ground.
Once lying down on the mat, inflation pressure could gradually be reduced by gently pressing on the “in” valve.
Silicone patches on its upper surface are a clever design feature, helping prevent sleeping bags from sliding off. It is also easy to deflate and pack away.
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What we don’t love
When inflated, it bends into a convex shape lengthways, meaning it doesn’t lie flat on the tent floor unless you put a sleeping bag and pillow on it.
You can feel the grooves of the air chambers – although they are barely perceptible once in a sleeping bag.
It’s not as comfortable as thicker, more premium sleeping pads I tested, but for the price it’s still very comfortable. Unlike many premium sleeping pads – and even its three-season cousin – the MT500 doesn’t come with an inflation sack. Instead, it is inflated by mouth via its one-way inflation valve. But this was easy, and took less than a minute.
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Sustainability
Like most inflatable mats, the MT500 is made from synthetic materials and laminated components that are hard to recycle at the end of their life. For products like this, the biggest environmental factor is usually how long it lasts. Five years of regular use is far better than replacing a cheaper mat every summer. This feels like a decent-quality mat, so if buyers use it regularly for several seasons, this will improve its sustainability profile. Although I have only slept on the mat once, hundreds of user reviews on Decathlon’s website give this mattress a solid 4.5/5, suggesting reliable durability.
Because it packs down small and is lightweight, transport emissions per unit shipped may also be lower than bulkier foam mats or flocked airbeds.
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Simond MT500: Should I buy it?
For the price, the Simond MT500 XL trekking mattress offers an excellent blend of comfort, packability and ease of use. It’s quick and straightforward to inflate by mouth, simple to deflate, and packs down small enough to slip easily into a rucksack, making it a practical option for everything from backpacking trips to festivals.
I felt adequately insulated from the ground during a late-April test, so it should see you comfortably through camping trips from late spring to early autumn. Colder nights, however, may require a mat with greater insulation.
This is still a budget camping mattress, and it won’t entirely disguise the fact you are sleeping on the ground. For a more luxurious night’s sleep, you might want to consider the Therm-a-Rest NeoLoft – our best camping mattress overall – or the Vango Shangri-La Lux 16 Grande, which is extremely comfortable but too bulky to carry in a rucksack. But at this price, the Simond MT500 is difficult to beat.
View at Decathlon***
Linda Geddes is a former Guardian science correspondent, known for inserting herself into her own mini-science experiments (like the time she brewed ant yoghurt from scratch). This extends to product testing, where she delights in devising rigorous ways to distinguish high-performance stuff from marketing puff. Outside work, she can frequently be found swimming in rivers, dangling from cliffs and trudging the dawn walk to the campsite Portaloo
