Attended Georgetown University with comedian Nick Kroll.
Writes the Stefon sketches on Weekend Update with Saturday Night Live cast member Bill Hader. Bill Hader and John Mulaney got the idea of Stefon from a shy café worker and a friend who opened many clubs that 'had everything'.
Grew up in Chicago.
Does not drink alcohol.
Mulaney attended St. Clement School and then St. Ignatius College Prep.
Parents are Ellen, a law professor, and Charles (Chip) W. Mulaney, Jr., an attorney.
Mulaney's maternal great-grandfather was George J. Bates, a mayor of Salem, Massachusetts, who also served as a congressman from that state.
Is a fan of the television show "Law & Order:SVU".
Studied English Literature at Georgetown University.
Owns a French Bulldog named Petuniafish.
Has two sisters and two brothers, the younger of which is deceased.