Cats stay warm in winter using their bodies, behavior, and help from the environment. Understanding these tricks also helps humans keep pet cats comfortable when it’s cold.
Natural body insulation
Cats have fur that traps a layer of air close to the skin, which acts as insulation and reduces heat loss. Many grow a slightly thicker or fluffier winter coat, and some develop a bit of extra body fat, both of which improve their ability to retain warmth.
Heat‑saving behaviors
Cats curl into a tight ball, tuck paws and tail under the body, and cover vulnerable areas like the belly to reduce exposed surface area and conserve heat. They also seek out warm spots such as sunny windowsills, high perches away from drafts, cozy beds, laps, and spaces near safe heat sources like radiators or warmed blankets.
Using shelters and nesting
Outdoor and feral cats stay warm by using insulated shelters or dens that trap their body heat, especially small, enclosed spaces lined with straw rather than blankets (which hold moisture and get cold). Indoor cats often do a similar thing on a smaller scale, choosing caves, boxes, and covered beds where their own body heat can quickly warm the space.
Metabolism and activity
To maintain normal body temperature in cold weather, a cat’s body uses more energy, so cats often eat a bit more in winter and convert that extra food into heat. Play and movement also generate warmth, so active bursts of running, pouncing, and climbing help raise their body temperature.
How humans can help
Humans help cats stay warm by providing draft‑free, elevated beds, blankets or towels on favorite resting spots, and—if needed—safe, pet‑rated heated pads or beds used under supervision. For outdoor cats, insulated shelters placed off the ground, plus regular access to unfrozen water and sufficient food, greatly improve comfort and safety in winter.
