Most squirrels do not disappear in winter; they either hunker down in snug nests high in trees or in cozy dens (sometimes in attics or wall cavities), coming out only briefly to eat stored food. A few species, mainly ground squirrels, actually hibernate underground for months at a time.

Winter squirrel basics

  • Tree and grey squirrels spend winter in dreys (leafy nests) or hollow trees that insulate them from wind and snow.
  • Ground squirrels dig burrows below the frost line and can hibernate for most of the season.
  • In cities and suburbs, squirrels may move into attics, garages, or wall cavities where it is warmer.

How they survive the cold

  • They “layer up” by putting on fat in fall, which works like an internal winter coat and energy reserve.
  • Squirrels cache nuts, seeds, and acorns in many small hiding spots, then dig them up even under snow using memory and smell.
  • On very cold days they stay in the nest for up to 18–20 hours, only venturing out during the warmest part of the day.

Do squirrels hibernate?

  • Tree squirrels and flying squirrels do not truly hibernate; their body temperature stays relatively stable, and they wake to eat stored food.
  • Ground squirrels enter deep hibernation, slowing their heart rate and metabolism and sleeping in underground dens for many weeks.
  • This is why people often assume “all squirrels hibernate” when in reality only some species do.

Winter social life

  • Squirrels are usually solitary, but in winter they often share nests or dens to pool body heat.
  • They may rotate between several dreys or cavities depending on weather and food access.
  • Around homes, this can mean more scratching sounds in ceilings or walls on very cold nights as they move around.

Fun forum-style note

“So cold, how do they manage in winter?”
Common answers in squirrel forums mention fattening up, nest-sharing, and quick food raids on milder days, matching what wildlife guides describe.

TL;DR: When you stop seeing them, squirrels are usually tucked into insulated tree nests, hollow trunks, or burrows (and sometimes your attic), living off stored food and body fat, with only some species truly hibernating.

Information gathered from public forums or data available on the internet and portrayed here.