Knock knock! Who’s there? Trick-or-treaters, and also tons of knock-knock jokes. There isn’t a single day of the year that more doors are knocked on than Halloween, so why not celebrate one of the most classic joke formats along with the holiday? Knock-Knock Jokes Day celebrates the knock-knock joke along with Halloween. Celebrate this holiday by sharing your best knock-knock jokes to all your trick-or-treaters. Or, if you’re the one doing the trick-or-treating, tell some jokes in exchange for candy!