Christmas cards should be mailed out by the end of November so they arrive at their destination in time for the holiday season. It's always a good idea to send them out early to allow for any potential delays or mistakes in delivery. Plus, sending cards early shows that you're thinking ahead and truly care about spreading Christmas cheer to your loved ones. So, get those cards in the mail by the end of November and make sure your loved ones have a merry and bright holiday season!