While Stonz Booties have no official temperature rating, they are widely used in Northern Canada, Eastern North America, Scandinavia, Finland and other cold regions. When paired with Stonz Bootie Liners, we have been told by countless customers that their little ones can play in the snow for long periods of time and stay warm and cozy! In places that experience more mild winters, Booties are great with as little as bare feet or socks.