Sam Bain (born 1971) is a British comedy writer, best known for the Channel 4 sitcom Peep Show. He attended a public school in London before graduating from the University of Manchester, where he met his writing partner Jesse Armstrong.
At the beginning of their writing career, Bain and Armstrong wrote for the Channel 4 sketch show Smack the Pony and the children's shows The Queen's Nose and My Parents Are Aliens. They went on to create and write Peep Show, BBC One sitcom The Old Guys, and most recently Channel 4 comedy-dramas Fresh Meat and Babylon. They also wrote for the Radio Four sketch show That Mitchell and Webb Sound, starring Peep Show's two main actors David Mitchell and Robert Webb, and its BBC Two adaptation That Mitchell and Webb Look. Peep Show has won several writing awards, including a BAFTA for Best Situation Comedy in 2008.
To date, Bain and Armstrong have written two films together — the 2007 comedy Magicians, and, alongside Chris Morris, the 2010 terrorism satire Four Lions.
Bain and Armstrong received the Writers' Guild of Great Britain Award at the British Comedy Awards 2010. In 2012 both Bain and Armstrong were featured on the TV industry journal Broadcast's 'Hot 100' list, highlighting the most successful people in UK television.