For many people, not really. Silk can feel comfortable because it can absorb and release some moisture, and it often feels cool against the skin, including when you use a silk pillowcase. That said, silk can feel warm for some sleepers, especially with a high weave density, a higher momme weight, or if your bedroom is already warm.

Your duvet, mattress, and ventilation often matter more than the pillowcase alone. If you sweat easily, choose a breathable silk pillowcase, avoid very thick options, and make sure there is good airflow in the room. Polyester “satin” can feel sweaty more often than real silk because it tends to ventilate less well.