Glove and Mitten Liners!
A pair of glove and mitten liners can add extra warmth to your current gloves or mittens. Liners not only add extra warmth but they can also help with keeping your hands dry which will also help your hands stay warm. Glove liners are nice to have on those cold days where you may need to take your glove off to answer a phone call or grab something out of your pocket, and you will still have the protection from the cold with your liner.
Some models of gloves and mitts come with a pair of liner gloves.