As a stand-up comedienne, McLennan has also received nominations for the Barry Award at the Melbourne International Comedy Festival and has performed internationally at the Edinburgh Fringe Festival.
As an actress, McLennan has appeared on shows such as Stingers, Offspring, Studio A, MDA and Dogstar. She has also performed both as a solo performer and as part of an ensemble in theatre, including the one-woman play Dead River, the musical Beaconsfield and I Coulda Been a Sailor. She starred in the web series Bleak, with her mother played by Denise Scott.
Kate has appeared twice on The Little Dum Dum Club. Her episode, the nineteenth, is particularly notable for its tell-all expose on Ben Elton's Live From Planet Earth, which had been cancelled just days before. The episode was published on March 2nd, 2011. She also appeared alongside Lawrence Mooney in the show's 99th episode.