Born in the United Kingdom, he worked as a journalist before joining Fox News in January 2004 as a business contributor, such as on Your World with Neil Cavuto.

During this time, he would help cover various events and had a short stint working as a voice actor for a dubbing firm founded by Matthew Oram, a fellow Radio Hong Kong broadcaster.

He continued to work for Radio Hong Kong before he began his broadcast journalism career at KEMO-TV (now KOFY-TV) in San Francisco.

On August 30, 2023, Fox Business announced that Varney would be a moderator of the second GOP Primary Debate alongside Dana Perino.

[6] In an interview on June 5, 2013 on Fox News, Varney said "We hand down $79 billion dollars every January on these so-called poor people."

This exchange of words gained brief popularity when it was cited on The Daily Show with Jon Stewart on Comedy Central, with journalists from The Washington Post reporting on his comments afterwards.

In 2013 Varney generated controversy for his commentary on Pope Francis, who had criticized the wealth gap and denounced unfettered capitalism as a system which "rules rather than serves.

"[15][16] In a December 2018 interview, Republican congressman Louie Gohmert repeated a false conspiracy theory about George Soros that he "turned on fellow Jews and helped take the property that they owned."