Ryan Murphy, who created the series with Brad Falchuk, confirmed that Bates will return for the fifth season of the acclaimed FX series.
Bates joins a cast that includes the previously announced Lady Gaga, Matt Bomer, Chloë Sevigny, Wes Bentley and Cheyenne Jackson. The upcoming season will be the first without Oscar winner Jessica Lange.
"American Horror Story: Hotel," slated to premiere on FX in October, is produced by Twentieth Century Fox Television. Production on the 13-episode season will begin in late summer.
Bates was nominated for a Tony for her performance in the original production of 'night, Mother.