The fourth Sonic movie now has an official release date: March 19th, 2027, according to Variety. Right around the release of the very successful Sonic the Hedgehog 3 last December, news hit that Sonic the Hedgehog 4 was in the works, but at the time, the movie only had a spring 2027 release window.
Sonic films have drawn all-star cast members over the years, such as Jim Carrey as Dr. Robotnik, who has played the role in all three of the movies, Idris Elba as Knuckles, and Keanu Reeves as Shadow. And a post-credits scene for the third movie hints that other fan favorites could join the series (spoilers in that link!), so there might be big casting announcements ahead for the fourth Sonic film.
The March 2027 date for Sonic The Hedgehog 4 means it will launch well after The Super Mario Bros. Movie sequel, which is set to debut on April 3rd, 2026.