Na versão americana do filme, a cidade se chama Zootopia. Quanto ao motivo pelo qual foi alterado no Reino Unido (e em alguns outros países, aparentemente), IMDB tem isto a dizer:
Why is Zootopia called "Zootropolis" in some countries?
This was a creative decision made by Disney stating: "to merely allow the film to have a unique title that works for UK audiences." Despite not having any connection to any similar movies or TV shows with similar titles, there is some speculation that it was to avoid confusion to an upcoming certain zoo in Denmark called "Zootopia" as well where its owners have had their trademark for the title since February 2010. Director Byron Howard also answered the question of why so many different titles: "Licensing or trademark conflicts. All the same movie."