A graduate of the University of Michigan and Northwestern University's Medill School of Journalism, Schefter was an editor at the Michigan Daily. After graduating from Medill, Schefter did an internship for the Seattle Post-Intelligencer before moving to Denver in 1990, when he began writing for The Denver Post.

Schefter joined the NFL Network in 2004 and appeared on NFL Total Access and also wrote for NFL.COM. Before joining NFL Network Schefter appeared frequently on ESPN's Around the Horn as a substitute for Woody Paige, who was based in Denver at the time (and has since returned). Before Around the Horn, Schefter appeared on ESPN's The Sports Reporters, where NFL Network executives first became familiar with his work. Schefter appeared on NBC twice in the summer of 2008, working as the sideline reporter for Al Michaels and John Madden during the Redskins-Colts Hall-of-Fame game and then the Redskins-Jaguars preseason finale.

According to a USA Today survey of fans published January 19, 2009: "NFL Network's Adam Schefter edged ESPN's Chris Mortensen (34%-32%) for best [NFL] insider despite the NFL Network being in less than half as many U.S. households."

It was announced on June 12, 2009 that Schefter had agreed to terms with ESPN to become a football analyst. He began appearing on air on August 17, 2009.