Having endured his first ever Premier League relegation, Sam Allardyce will leave West Brom after Sunday's game away to Leeds.
The club confirmed his impending departure after Wednesday night's 3-1 defeat at home to one of his former sides West Ham.
Allardyce took the reins at The Hawthorns with the task of maintaining the Baggies' Premier League status.
Despite an April revival that saw them record back-to-back wins against Chelsea and Southampton, West Brom's relegation was confirmed three games before the season's end with a 3-1 defeat at Arsenal.
Long-time deputy Sammy Lee and first-team coach Robbie Stockdale will also leave their positions after Sunday's final game of the season.
Sporting and technical director, Luke Dowling, said: “Sam, Sammy and Robbie came in at a really difficult time for the football club and worked tirelessly in their efforts to keep the club in the Premier League.
“Unfortunately, collectively, we were unable to achieve our goal of surviving relegation. In the second half of the season we played with passion and desire, delivering some memorable results with organised, entertaining football.
“Ultimately, we were unable to accumulate the points total required to keep us here, but Sam certainly restored pride with a number of resilient displays.
“Sam, Ken (Chief Executive, Xu Ke) and I have discussed at length our plans for the future and we very much hoped to have Sam in charge for next season and beyond.
“Sam and his coaching staff have been excellent to work with and I would like to thank them all for their efforts.
“Sam has given his reasons for leaving and we respect his decision. He has been brilliant to work with and I wish him, Sammy and Robbie all the very best in the future. They will always be welcome at The Hawthorns.”