Lachlan Buchanan was born in Australia in 1990. Buchanan attended Maleny State School and Matthew Flinders Anglican College. Buchanan acted in soap operas such as Home and Away. He has also acted in several films, with support roles in Arcadia Lost and All My Friends Are Leaving Brisbane; and as a lead in Newcastle.
Buchanan played Scott Mitchell in the first CMT sitcom Working Class, which premiered in January 2011.
He is an experienced surfer, and did half his surfing scenes in Newcastle himself. He is fluent in French.
As of 2010, he is based in Los Angeles.
In 2015 Buchanan starred in the Low Budgetfilm, Muck, released in March. Buchanan was cast in the role of Kyle Abbott on the American soap opera, The Young and the Restless. His first scene aired on 25 February 2015.
In January, 2016, Buchanan was announced to guest star in one episode of MTV's Teen Wolf, as Henri Argent. Henri is a recluse who lives in a forest grove and has been described as "wise but guarded". Being an Argent, Henri is said to know a lot about the supernatural world.