The West Coast offense is a scheme popularized back in the 1980s by Hall of Fame and Super Bowl-winning coach Bill Walsh during his tenure as head coach of the San Francisco 49ers. During his time with the 49ers, he won three Super Bowls. Using the West Coast offense the 49ers dominated the NFL.
The West Coast Offense or WCO at its core prioritizes passing over running. WCO relies on a short and quick passing attack and very select running plays. It is based on controlling the tempo of the game, moving quickly to tire out the defense, and (at the time of its creation) untraditional routes and motions on the line.
The West Coast Offense is grounded in its formation and three to five-step dropbacks by the quarterback. These 3-step and 5-step drops are now a routine in today's game. WCO changes running backs and tight ends to receivers. Running backs and tight ends now either are coming out of the backfield running swing or curl/hitch routes or join the wide receivers and everyone spreads out wide across the line. WCO uses multiple backs behind the line of scrimmage.
These short routes are synchronized to match the quarterback's dropbacks, which enables short and easy completions that are perfectly timed. This aggressive passing attack puts the defense on its heels which allows for a running game based in trap, counter, toss plays to develop. And once the defense is forced to play the run, now comes a significant play design that came out of WCO called "play-pass" or play action. The play action pass is the best call against the most disciplined defense Walsh believed. All of a sudden 3-5 yard completions and short running plays opened up the possibility for a huge play downfield.
These different elements and play calls, although varied in their execution are manageable for quarterbacks and coordinators to implement. Walsh only ran the same few plays during the course of the game. The same formation and speed make it challenging for opposing defenses to catch on.
Today's NFL and many teams since Walsh's 49ers use the West Coast scheme. Andy Reid has implemented his own WCO in Kansas City with the Chiefs, who in 2018 were the NFL number one scoring offense and whose quarterback Patrick Mahomes threw for over 5,000 passing yards and 50 touchdowns. Another current powerhouse team that uses the WCO is the Los Angles Rams, who lead by football genius Sean McVay, played in the 2018 Super Bowl.