The conference has produced 11 Supporters' Shield champions and 18 MLS Cup winners in Major League Soccer's first 29 seasons.
Changes from 2005: The San Jose Earthquakes was put on hiatus; The Houston Dynamo joined the league as an expansion franchise.
Changes from 2010: The Portland Timbers and Vancouver Whitecaps FC were added in the 2011 expansion; Houston Dynamo moved to the Eastern Conference.
Changes from 2014: Chivas USA ceases operations; Sporting Kansas City and the Houston Dynamo move in from the Eastern Conference.
Changes from 2019: Nashville SC was added in the 2020 expansion, but moved to the Eastern Conference since the MLS is Back Tournament up to the end of the 2020 season.
From 2015 to 2021, the Western Conference was represented in the MLS Cup by either Seattle Sounders FC or the Portland Timbers.
† – The LA Galaxy were declared winners of the Western Division in 2001 after the September 11, 2001 terrorist attacks forced the cancellation of the rest of the regular season.
In total, the MLS West all-star team has 1 win, 1 draw, and 4 losses against the east.