Sampson was born and raised in Houston, Texas as the son of Daphne Smith Sampson and Hoyle Sampson, Sr. He revealed that he had always been interested in the arts and his mother enrolled him in music lessons because he comes from a family of musicians and artists. Daphne used to play the piano for him as a child. He expressed an interest in acting when he was around 10 after he saw a Gap commercial. His mother told him they needed to find an agent and that agent referred him to the Kim Terry Studio in Texas. He eventually started performing in the theater program in high school at Elkins High School (Texas).
He is a devout Christian.
In 2008, he appeared in two episodes of the ABC Family series Greek and followed that up with an episode of CSI: Crime Scene Investigation in 2010.
In July 2013, he booked the recurring role of Jesse in the fifth season of The CW series, The Vampire Diaries.
In January 2014, Sampson was cast in the role of Dean Iverson in the Fox miniseries, Gracepoint.
In early 2015, Sampson shot the pilot for a potential ABC series called The Kingmakers but the series wasn't picked up.
In July 2015, Sampson booked the recurring role of Caleb Hapstall in season 2 of ABC's prime time legal drama, How to Get Away with Murder, produced by Shonda Rhimes.
He has also started his own production company called Sampson Studios.