[1] Telfer attended Rancho Cucamonga High School, where he received a 3.5 grade point average.

His height and swiftness led to his being cast as a wide receiver, but he was so poor at catching footballs that he didn't play that year.

[3] Head coach Pete Carroll successfully recruited Telfer for the University of Southern California (USC),[4] where he attended upon receiving an athletic scholarship.

[2] He was redshirted his freshman year (the 2010 season), after which Carroll left USC to coach professionally for the Seattle Seahawks.

[2] In his junior year, USC began the season ranked Number 1 in the USA Today Coaches' Poll.

A violent altercation (which some media reported as a fistfight, while others said it was verbal) broke out in the USC locker room after the game, in which some younger players criticized senior quarterback Matt Barkley for not playing even though injured and for generally poor leadership throughout the season.

[6] USC lost three of its first five games of Telfer's senior season, and Kiffin was fired as head coach on September 29, 2013.

[2] His USC teammates voted to give him the Chris Carlisle Courage Award for starting every game his final year, despite his significant injuries.

[9] Randall Telfer graduated from the University of Southern California in 2013 with a bachelor's degree in political science.

[13] On July 28, 2015, head coach Mike Pettine announced that Telfer would sit out training camp and remain idle until at least midseason.

[14] Telfer played 14 games in the 2016 season under new head coach Hue Jackson, catching two passes for four yards[15] and spending most of his time as a blocker.