Krause was born in El Toro, California, the younger of two children of Alice and Jeff Krause. He is adopted.[1] His elder brother is named Patrick. He grew up in Southern California and took his first acting class at The Actors Workshop while in junior high. In his teens, he studied karate and attended El Toro High School, where he graduated in 1987. He continued his education at Orange Coast College.

Krause landed his first role in 1989 as a student in the TV series TV 101. He then starred in the made-for-TV-movie Match Point, the CBS Schoolbreak Special “American Eyes”, and An American Summer, before landing his first major role as Richard Lestrange, Jr. in the film Return to the Blue Lagoon (1991). He was a co-star in the Bandit series prior to his most notable role of Leo Wyatt, in The WB Network series Charmed (1998–2006). Krause originally auditioned for the role of Andy Trudeau but was cast as Piper’s handyman/whitelighter love interest.