David Moyes will leave West Ham at the end of the season.
Moyes announced the decision on Monday night.
"I have enjoyed four and a half brilliant years at West Ham, and the club is in a stronger position than when I returned back in 2019," Moyes said.
When I joined West Ham for a second time, the club was one place above the relegation zone, and it has been a terrific journey to have achieved three consecutive seasons in Europe.
"I would like to thank all the players for their support, and all the success they have achieved, over the last four and a half years."
The club's joint chairman David Sullivan said: "David has been an absolute professional to work with and he will leave with our greatest respect and good wishes he deserves to be held in the highest esteem for the service he has given to West Ham United, and we wish him every success in the future.
"By making this announcement now, it allows David to get the send-off he deserves from the West Ham supporters and for us all to show our appreciation to him at our final home fixture of the season against Luton Town on Saturday."
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