Showbiz
Rex Features
The actor and comedian made the announcement at the premiere of Paper Heart in New York, adding that the baby is due in September.
Speaking to People, he said: "I'm really excited. I think it's going to be awesome."
The star went on to joke that he will be the only current SNL cast member to have a child, saying: "Everybody will have to understand when I'm really tired! Kidding - I'm actually handling it well... [My wife] is awesome. Way tougher than I am."
Hader tied the knot with Maggie Carey nearly three years ago.
He recently starred alongside Ben Stiller in Night At The Museum 2, and has also appeared in Knocked Up, Superbad and Forgetting Sarah Marshall.
More: Bill Hader, Showbiz
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