Thomas is among nine new full-time officials hired by the NFL for the upcoming 2015 season. Her hiring was first reported last week by Aaron Wilson of the Baltimore Sun.
Thomas had been working as a college football referee for eight years in Conference USA. She became the first woman to officiate a major college football game when she worked a contest between Memphis and Jacksonville State in 2007.
Thomas, 41, will not be the first female official to work an NFL game, however. During the officiating lockout in 2012, the league hired Shannon Eastin as a temporary, non-union official. She officiated a regular-season game between St. Louis and Detroit.
The eight other officials hired by the NFL on Wednesday: Line judge Kevin Codey; head linesmen Hugo Cruz and Bart Longson; umpire Clay Martin; side judges Walt Coleman IV, Aaron Santi and Jabir Walker; and field judge Shawn Smith.
Times staff writer Sam Farmer contributed to this report.