Side sleepers need a thick pad – minimum 3 inches.

Yes. If you sleep on your side and backpack, you need a pad at least 3 inches thick. Otherwise you’ll wake up with a sore hip and shoulder, and that’s not worth saving a few ounces.

The issue is pressure points. On your side, your hip and shoulder dig into the pad. Thin pads (under 2.5 inches) let you bottom out against the ground. That hurts. Thick pads (3+ inches) let those bony parts sink in without hitting dirt. Your spine stays aligned — that’s the whole game.

You’ll also want an R-value of at least 4 if you sleep cold. Side sleepers lose more heat because more of your body is off the pad (gaps around your waist, knees). A warmer pad helps. But thickness is the non-negotiable. I’ve tried a 2-inch pad as a side sleeper — woke up every hour. Switched to a 3.5-inch Nemo Tensor and it changed my trips.

Trade-off: weight. Thicker pads weigh more and pack bigger. You’ll probably be around 16–20 oz for a good one. The Therm-a-Rest NeoAir XTherm (3 inches, R-6.9) is the gold standard for warmth and weight. The Exped Ultra 3R (3.1 inches, R-3.5) is cheaper and comfier but a little heavier.