American League West

Current members

 * Houston Astros - Joined in 2013; formerly from the National League West (1969-1993) and National League Central(1994-2012)
 * Los Angeles Angels of Anahiem – Founding member (as the California Angels)
 * Oakland Athletics – Founding member
 * Seattle Mariners – Joined in 1977 as an expansion team
 * Texas Rangers – Joined in 1972; formerly of the American League East (as the Washington Senators)

Former members

 * Chicago White Sox – Founding member; moved to the American League Central in 1994
 * Kansas City Royals – Founding member; moved to the American League Central in 1994
 * Minnesota Twins – Founding member; moved to the American League Central in 1994
 * Milwaukee Brewers – Founding member (as Seattle Pilots); moved to the AL East in 1972, then to the AL Central in 1994. Eventually moved to the NL Central in 1998.