College and amateur Beitashour graduated from
Leland High School in 2005 where his number 3 jersey was later retired, becoming only the second Leland athlete after
Pat Tillman to have a jersey retired. Steven was the
captain of his high school's
varsity team and was their leading goalscorer his junior and senior years in the
number 10 role. In his graduating year at Leland, Beitashour received the inaugural Pat Tillman Award, given to a
Bay Area student for outstanding achievements in both athletics and academics. During his late college years, Beitashour also played for the
San Jose Frogs in the
Premier Development League. He graduated from San Diego State in December 2009. He made his professional debut on April 10, 2010, in a 2–1 win against the
Chicago Fire, and scored his first professional goal on April 24, 2010, against
Chivas USA. Beitashour was selected for the
2012 MLS All-Star Game and played the full 90 minutes against
Chelsea in the 3–2 win. The Earthquakes won the
2012 MLS Supporters' Shield with Beitashour starting in all 33 of his regular season appearances and leading the league with 110
crosses that season. He provided 16
assists in his last 3 years with the Earthquakes, more than any other
MLS defender during the same time period.
Vancouver Whitecaps FC Vancouver Whitecaps FC acquired Beitashour for an undisclosed amount on January 27, 2014. On March 8, Beitashour played his first match for the Whitecaps in their
season opener against the
New York Red Bulls, providing a secondary assist to
Kenny Miller in their 4–1 win. Beitashour was named in the MLS team of the week after his performance against the
LA Galaxy on April 19. On April 26, he provided a game-tying assist to
Sebastián Fernández in the last minute of the match against
Real Salt Lake. Beitashour was nominated for the
2014 MLS All-Star Game against
Bayern Munich. On September 27, he provided a game-winning assist to
Pedro Morales in a 2–1 win against
Real Salt Lake. On October 10, the Whitecaps won the
2014 Cascadia Cup with a 1–0 win at
Seattle Sounders FC. The Whitecaps also qualified for the
2015–16 CONCACAF Champions League as the best Canadian team of the
regular season. Prior to the start of the
2015 MLS season, Beitashour was the Whitecaps'
players union representative. On March 14, 2015, in the second game of the
Whitecaps' 2015 season, Beitashour provided an assist to
Octavio Rivero during the 86th minute in a 1–0 win over the
Chicago Fire. On July 29, 2015, Beitashour and his Whitecaps teammates attended a
charity event for children in
Nanaimo. On August 26, 2015, the Whitecaps won the
2015 Canadian Championship to qualify for the
2016–17 CONCACAF Champions League.
Toronto FC Beitashour was traded to
Toronto FC during the 2015–16 off-season for TFC's second round selection in the
2016 MLS SuperDraft. He made his debut for Toronto FC in a 2–0 win over the New York Red Bulls on March 6, 2016. On November 30, 2016, Beitashour provided an assist to
Benoît Cheyrou to clinch the
Eastern Conference title during the
2016 MLS Cup Playoffs. On October 22, 2017, Toronto FC won the
Supporters' Shield, breaking the MLS record for the most points in a single season. On December 9, 2017, Beitashour won the
2017 MLS Cup with Toronto FC for the first time in the club's history, becoming the first MLS team to complete a
domestic treble.
Los Angeles FC In January 2018, Beitashour signed with
Los Angeles FC for their
inaugural season. He provided two assists in their second match before providing another one in their following match to
Carlos Vela in the first
El Tráfico derby. He scored his first goal for LAFC on May 5, 2018, against
FC Dallas. He scored his second goal for the club on June 9, 2018, against his hometown club, the
San Jose Earthquakes. In October 2018, LAFC unveiled a
Persian language T-shirt in honor of Beitashour. In September 2019, Beitashour and LAFC won the club's first major trophy with the
Supporters' Shield.
Colorado Rapids On September 19, 2020, Beitashour signed a one-year deal with
Colorado Rapids as a
free agent. In December 2020, Beitashour signed a one-year contract extension with the Rapids ahead of the
2021 Major League Soccer season. He made his club debut on July 21, 2021, in a league match against
FC Dallas. Having scored five goals and provided 38 assists across 258 regular-season games in his MLS career, Beitashour re-signed with the Rapids on January 7, 2022, for the
2022 Major League Soccer season. On November 10, 2022, his contract option was declined by Colorado. On December 13, 2022, the Colorado Rapids re-signed Beitashour for the
2023 Major League Soccer season. On November 28, 2023, his contract option was declined by Colorado. On December 13, 2023, Beitashour announced his retirement. ==International career==