A sleeping mask is a leave-on overnight treatment that delivers deep hydration and active ingredients to your skin while you sleep. It's typically thicker and richer than a regular moisturiser and is meant to replace (not be added on top of) your night cream.
Sleeping masks work because they create an occlusive layer on top of your skin, preventing moisture from evaporating overnight. They also take advantage of the fact that your skin's repair processes are most active while you sleep, so you're delivering ingredients at the optimal time.
Use a sleeping mask 2 to 4 times a week, not necessarily every night. Apply as the last step of your evening routine, give it a few minutes to absorb before getting into bed, and rinse off in the morning if it feels heavy. Otherwise, it's fine to leave on.
Cult favourites in our community: Laneige Water Sleeping Mask (the OG), COSRX Snail Mucin All-in-One Cream as a lightweight night option, and Numbuzin No.3 Skin Softening Serum-Toner mask for sensitive skin.