The singer will replace CeeLo Green as a coach on The Voice season 7, the show announced Monday on Twitter.
"This is going to be so fun," Williams posted to his own Twitter account as a reply to the announcement.
Williams, 40, was welcomed to the singing competition via Twitter by PEOPLE's Sexiest Man Alive, Adam Levine.
"@Pharrell Welcome to the circus dude!" he wrote.
Usher joined the online welcome, writing, "Congratulations to my brother @Pharrell for joining #TheVoice as a new judge on Season 7. RT to show my boy some love! #Happy"
In addition to Levine and Usher, season 6 coaches include Blake Shelton and Shakira.
No word as to whether Christina Aguilera will return to the show next season. The pop star is expecting with her second child – a girl! – and got engaged to Matt Rutler in February.