It's best to remove your Christmas lights and decorations before the end of the holiday season. You can wait until after the new year, but it's generally recommended to have them taken down before then. This will help prevent damage to your decorations from the elements and also give you time to store them properly for next year. It's also a good idea to take down your lights while they're still in good condition, as it's more difficult to repair them once they've been damaged by the cold.