Born in Nottingham, England, his family emigrated to Canada when he was young where he later studied at McGill University. Between 1980 and 1981, he studied Russian at Harvard, and in 1984 he studied Chinese at Cambridge University. From 1998 to 1999, he was a visiting fellow at King's College, Cambridge, studying Islamic history and culture. He also speaks French and German. His father was a South African who served in the Royal Air Force.
In the early 1970s, Burns wrote for the Canadian Globe and Mail, as a local and later parliamentary reporter. He was sent to China in 1971 to be among one of few Western journalists in China during the Cultural Revolution, after a confusion that led to his brief ban from the precincts of the Canadian Parliament by the Commons Speaker. Burns joined The New York Times in 1975, reporting, at first, for the paper's metropolitan section, and has written ever since for the newspaper in various capacities.
He has been assigned to and headed several of the Times foreign bureaus. He and fellow Times journalists John Darnton and Michael T. Kaufman won the 1978 George Polk Award for foreign reporting for coverage of Africa. Burns was the Times bureau chief in Moscow from 1981-84. In 1986, while chief of the Times Beijing bureau, Burns was incarcerated on suspicion of espionage by the Chinese government. Charges were dropped after an investigation, but Burns was subsequently expelled from the country.
In the early to mid-1990s, Burns head the New York Times' bureau in New Delhi, with responsibility for the Indian Subcontinent and adjoining regions, from Afghanistan to Burma. He and his family resided in New Delhi though Burns was frequently on the road, travelling regularly to Kabul, Islamabad, Dhaka, Colombo and Kathmandu. He actively covered events in Afghanistan, which led to his second Pulitzer in 1997, this time "For his courageous and insightful coverage of the harrowing regime imposed on Afghanistan by the Taliban". Burns was based in Baghdad during the lead up to the Iraq war in 2003 and has written extensively on the war and the subsequent occupation. In July 2007, Burns succeeded Alan Cowell as bureau chief in London. On 30 September 2007, Burns received the Elijah Parish Lovejoy Award as well as an honorary Doctor of Laws degree from Colby College.
Burns is a frequent contributor to PBS, including a number of appearances on the Charlie Rose show and The NewsHour with Jim Lehrer via satellite from Afghanistan and Iraq. In a January 2009 interview, Michael Barone called Burns "one of the great foreign correspondents of our time". In an August 2010 interview with Charlie Rose, Christopher Hitchens, while recounting a tour of Sarajevo guided by Burns in which they were fired upon, called Burns "the greatest war correspondent of our time".
On 26 March 2015, The New York Times announced that an article about the burial of Richard III would conclude Burns' career at the New York Times.
In an October 2008 interview with the Russian Ambassador to Afghanistan, Zamir Kabulov, Burns accused Kabulov of being a KGB operative.
Burns was awarded the 1993 Pulitzer Prize for International Reporting citing "his courageous and thorough coverage of the destruction of Sarajevo and the barbarous killings in the war in Bosnia-Herzegovina".
Burns is married to Jane Scott-Long, who manages the New York Times' Baghdad Bureau.