Yes, they can be used during winter. But you must make sure that your trailer is one of those equipped adequately for winter as there are travel trailers that are not sufficiently prepared for this season. It is also a must to make sure that the water won't freeze in winter. You can buy heating pads to prevent them from freezing so that you'll have water to use while you're out enjoying the snow and winter. You can also consult your dealer to give you more information regarding winter traveling for your travel trailer and for you to be ready for whatever emergency you might encounter.