Gallagher studied at the University of San Diego and he majored in business[1] playing quarterback for the Torero football team.
[2] Based in Los Angeles, Gallagher served as a co-anchor (with Martha MacCallum) of The Live Desk and as a substitute anchor for Studio B with Shepard Smith and Fox Report.
During his time at Fox, Gallagher has reported on the Space Shuttle Columbia disaster and the 2004 Southeast Asian tsunami.
He has worked at Fox's Chicago, San Francisco, and New York City news bureaus.
Previously Gallagher worked at WCPX (now WKMG) in Orlando, KVBC (now KSNV) in Las Vegas, and KTVB in Boise.