The program will air Mondays through Thursdays at 11 p.m. Eastern, shifting TBS’ “Lopez Tonight,” starring George Lopez, to midnight.
The surprise announcement hit the same day O’Brien starts a two-month, North American comedy tour in Eugene, Ore., amid persistent reports that he was likely to claim Fox as his new late-night home.
Barring Fox, syndication was widely considered O’Brien’s most likely option. Few if anyone mentioned TBS as a plausible destination.
O’Brien began serious talks with TBS just last week, the network said.
O’Brien left NBC in January after hosting “The Tonight Show” for just eight months, as his ratings plunged from those of his longtime “Tonight” predecessor, Jay Leno, who reclaimed the hour. Until last June, O’Brien had followed Leno as host of “Late Night” since 1993.
After giving O’Brien “Tonight,” NBC sought to keep Leno on board with a prime-time show that quickly flopped. An attempt to move O’Brien to a post-midnight slot drew O’Brien’s ire, and he walked away with a $32 million settlement package.