The Halloween update in Animal Crossing: New Horizons gives you the chance to go trick-or-treating at the end of the month. The big event doesn’t happen until October 31, but you have plenty of time to prepare for it. You want to make sure you visit Nook’s Cranny every day to receive a piece of candy to use during the main event. Also, when the event arrives, you don’t want to be the odd-one-out and make sure to create a Halloween costume.
There’s no specific item that says, “Halloween costume.” Instead, you want to rely on creating your choice from various outfits available at the Able Sisters shop. Walk inside, and you can choose from a rotating selection of clothing, much like you would during any other season. Make sure to check back every day as the Able Sisters’ selection usually includes at least one item you can use for Halloween, such as a Hotdog costume or an animal outfit. There are no limits to what can be considered a Halloween costume.
When the Halloween event in Animal Crossing: New Horizons happens on October 31, from 5 PM to midnight, you can participate in the festivities with the rest of the residents on your island. You give out candy, accept it, and interact with everyone who lives there. Make sure to bring your costume to the event, and don’t be late.