Party City is a popular chain of party stores in the United States that provides a wide array of party supplies, costumes, and special occasion items. Founded by Steve Mandell in East Hanover, New Jersey, in 1986, the business quickly expanded beyond its initial 4,000-square-foot store to open more branches. Recognizing the potential of Halloween, Mandell focused on this holiday in the early years, a decision that proved to be successful. Today, Halloween continues to play a significant role in Party City's operations, with around 300 Halloween City pop-up stores opening annually. In 1990, Mandell transformed Party City into a franchise, leading to rapid expansion and the establishment of 58 locations within three years. Currently, Party City is the largest retailer of party goods in North America, boasting over 900 outlets that offer a diverse range of supplies in different colors and themes, including licensed characters and sports teams. The store also caters to holidays and special events such as baby showers, graduations, and weddings. Halloween costumes are consistently available throughout the year, and some Party City stores provide in-store helium balloon filling and even balloon delivery services.