Do You Need a Sleeping Pad on a Cot? Yes, Below About 50F
A cot has no insulation and air moves under it. Above 60F a bare cot is fine; from 45 to 60F add a pad; below that, R 4 or more, on top, as wide as the deck.
Yes, for most of the year. A cot gets you off the ground, but its fabric deck has no insulation and air moves freely underneath it, so the only thing between you and the night air is your sleeping bag, and the part under your body is squashed flat. On nights above roughly 60F a bare cot is fine, and that airflow is why it sleeps cooler than the ground. Between about 45 and 60F most people want a pad on top. Below about 45F you need one, with an R-value of 4 or more. The pad goes on top of the cot, not under it, and it should be as wide as the cot deck. Those temperatures are rules of thumb from pad makers’ R-value guidance and user reports, not test results.
When a bare cot is fine, and when it is not
A pad cushions and it insulates. On the ground the insulation sits between you and cold earth. On a cot the deck is a sheet of polyester with nothing inside it, and the air under it moves with every draft through the tent, carrying heat away faster than still air would. Nemo’s R-value explainer describes R-value as resistance to heat flowing from a warm body through the pad. A cot deck has close to none.
On a July night at 65F the air under the cot is a feature; the same cot in October at 40F is a cold bed. The dividing line is about 50F. Above 60F any pad is for comfort. From 45 to 60F, the range most spring and fall family camping falls in, a modest pad on top is the difference between a good night and a 3 a.m. search for a jacket. Below 45F the pad is not optional.
On top, not underneath
The pad goes on the deck, under your sleeping bag. People regularly ask whether a pad or blanket slung underneath the cot helps. Almost not at all: it insulates the ground, and the ground is not what is losing heat. You are, to the air, and anything hung below the cot still leaves moving air between it and you.
Which R-value for which nights
R-value is the standardized measure of a pad’s insulation, tested to ASTM F3340 by the major makers, so a 4 from one brand means the same as a 4 from another. Therm-a-Rest’s published chart puts R 1 at summer, R 2 at the start of three-season use, R 4 at all-season and R 6 at extreme cold. Those bands assume a pad on the ground; a cot in moving air is, if anything, harsher, so round up. Nemo adds that R-values are additive, so a foam pad under a self-inflating pad gives you the sum.
| Expected night low | Pad on the cot |
|---|---|
| Above 60F | None, or a thin foam pad (R 1 to 2) for comfort |
| 45 to 60F | R 2 to 3 |
| 25 to 45F | R 4 to 5 |
| Below 25F | R 5 or more, or two pads stacked |
The temperatures are our reading of the makers’ season bands, not numbers any maker publishes. If you sleep cold, or the sleeper is a child, move one row down.
Match the pad to the cot deck
Width first: a “sleeping pad for cot” is whatever matches the deck, and decks vary. A backpacking cot like the Helinox Lite Cot is 23 inches wide and 73.5 long, rated to 265 lb. A full-size folding cot like the Coleman Pack-Away has an 80 by 32 inch sleeping area and a 300 lb rating. Most folding camp cots fall between the two; use the listing’s sleeping-area width, not the overall width with the frame. Pads come 20, 25 and 30 inches wide; match the deck within an inch or two. A 20 inch pad on a 30 inch deck leaves five inches of bare fabric each side, exactly where a side sleeper’s shoulders and elbows go. A pad wider than the deck hangs over the rail and folds down at night. Shorter than the deck is fine; longer bends over the end bar. If you sleep on your side, thickness matters as much as width on a firm deck; the best sleeping pad for side sleepers covers that.
That also answers the two mattress questions. Does a camp cot need a mattress? A 2 to 3 inch self-inflating pad is the mattress. Can you put an air mattress on a cot? A household air mattress is sized for a bed frame, not a cot deck, so it overhangs both rails and rocks on the frame. It also has no insulation, so it fixes the comfort problem and not the cold one. It is the wrong tool.
Foam, self-inflating or air, and the sliding problem
Closed-cell foam is the cheapest and the most forgiving on a cot: a frame rail cannot puncture it and its textured surface grips the fabric. It is also the least warm per inch. The Nemo Switchback is 0.9 inches thick and rated R 2, a comfort layer in summer and a cold bed in November.
Self-inflating pads have a foam core that gives R 4 to 6 without much thickness, a fabric top that grips the deck, and a shell that shrugs off frame edges. That is why they are what most cot owners end up with. The price is weight: a 30 inch self-inflater is a 4 lb object.
Air pads are the lightest and warmest per ounce and the ones that cause trouble on a cot. User reports say the same three things: the slick shell slides on cot polyester, a thick air pad feels bouncy on a tight deck, and on a loose deck it sags into the hammock shape the cot already had. A frame rail can also puncture one.
The fix for any pad that moves is to pin it to the deck: a fitted cot sheet stretched over both pad and deck, two cam straps around them at the chest and knees, or a strip of rubber rug underlay between pad and deck.
Pads that fit a cot
Three pads, one per deck width and budget, chosen on the constraints above. Specs are from the makers’ and retailers’ pages; none was tested by us.
Therm-a-Rest Trail Pro (Regular Wide)
A 25 by 72 inch self-inflating pad, 3 inches thick, R 4.4, 2 lb 5 oz, with a 50D polyester knit top that stays put on a fabric deck. It is the default for a 24 to 26 inch deck: warm enough for the 25 to 45F row on its own and thick enough to hide the deck’s sag. Check price on Amazon
Therm-a-Rest BaseCamp (XLarge)
The wide one: 30 by 77 inches, 2 inches of self-inflating foam, R 6, 4 lb, 75D polyester both faces, listed at $119.95. It covers a 30 to 32 inch deck like the Coleman’s edge to edge and reaches the below-25F row without a second pad. A 25 by 77 inch Large (3 lb 6 oz) gives the same R 6 on a narrower cot. Check price on Amazon
Nemo Switchback
A 20 by 72 inch closed-cell foam pad, 0.9 inches thick, R 2, 14.5 oz, about $55 to $60. It is the warm-weather comfort layer, the pad for a child’s cot, and the cheapest way to add R 2 under a self-inflater on a cold night. Alone, it is not a winter pad. Check price on Amazon
Kids on cots
Same rule, same number: below 50F the child’s pad goes on top of the cot, not in the car. Kids’ cots run 24 to 25 inches wide, so a 20 inch pad like the Switchback leaves only a couple of inches of bare fabric each side, a reasonable match for a child. For a child, use the next row down in the table. Whether a child needs a cot at all, and what to do about rolling off one, is in the best camping cot for kids.
Where this setup lives: tents, truck beds and the car
A cot plus a pad is a tent setup first and a truck-bed setup second. The 73.5 inch Helinox fits lengthwise in a 6.5 ft bed under a cap or bed tent; the 80 inch Coleman needs an 8 ft bed. Inside an SUV there is no room for legs and no need for them: the cargo floor is the cot, and a thick pad alone is the answer, which is the subject of the best car camping mattress by vehicle size and the rest of car, truck and SUV camping. If the width question is about your body rather than the cot, sleeping pads for plus-size campers covers that side.