Nicholas John Gillespie (; born August 7, 1963) is an American libertarian journalist who was editor-in-chief of Reason magazine from 2000 to 2008 and editor-in-chief of Reason.com and Reason TV from 2008 to 2017. Gillespie originally joined Reason's staff in 1993 as an assistant editor and ascended to the top slot in 2000. He is currently an editor-at-large at Reason. Gillespie has edited one anthology, Choice: The Best of Reason.