Hi Phoebe,
Welcome to the Disney Parks Moms Panel and thank you for sending us your question.
Mickey's Not-So-Scary Halloween Party at Magic Kingdom Park is my absolute favourite special event at Walt Disney World Resort, you will absolutely love it!
In order to attend Mickey's Not-So-Scary Halloween Party all guests require a Special Event Ticket. If you are planning on visiting Magic Kingdom Park on the day of the Party, and do not have a Ticket for Mickey's Not-So-Scary Halloween Party, you will be asked to leave once the party officially starts at 7:00. Everyone attending Mickey's Not-So-Scary Halloween Party will be given a bracelet to verify admission and if you are not wearing one of the bracelets, you will be asked to exit the Theme Park. Cast Members will also scan your MagicBands at the entrances of attractions, and if you do not have a ticket for the Special Event, you will not be granted access to the attraction. You can purchase your tickets to Mickey's Not-So-Scary Halloween Party by calling (407) 939-1872 in the United States and Canada, or 0800 08 50 582 from the United Kingdom.
What my family likes to do is enjoy a quiet day at our Walt Disney World Resort Hotel and head over to Mickey's Not-So-Scary Halloween Party for 4:00. At that time, Cast Members typically allow guests with a Special Event Ticket to enter Magic Kingdom Park, and we don't have to use an extra day of our regular Theme Park Tickets. I find it gives us enough time to enjoy all of our must-do attractions, as well as the special party-related events as well.
I hope you have a magical time at Walt Disney World Resort, Phoebe. Please let us know if you have any other questions, we are always happy to help.
Stephanie