diff --git a/clientapi/routing/routing.go b/clientapi/routing/routing.go
index cb2a67bca..ec90b80db 100644
--- a/clientapi/routing/routing.go
+++ b/clientapi/routing/routing.go
@@ -152,6 +152,9 @@ func Setup(
 			}
 			return util.JSONResponse{
 				Code: 200,
+				JSON: map[string]interface{}{
+					"affected": res.Affected,
+				},
 			}
 		}),
 	).Methods(http.MethodGet, http.MethodOptions)
diff --git a/roomserver/api/perform.go b/roomserver/api/perform.go
index 3efba59e1..30aa2cf1b 100644
--- a/roomserver/api/perform.go
+++ b/roomserver/api/perform.go
@@ -220,5 +220,6 @@ type PerformAdminEvacuateRoomRequest struct {
 }
 
 type PerformAdminEvacuateRoomResponse struct {
-	Error *PerformError
+	Affected []string `json:"affected"`
+	Error    *PerformError
 }
diff --git a/roomserver/internal/perform/perform_admin.go b/roomserver/internal/perform/perform_admin.go
index aa0006489..27a5d71f0 100644
--- a/roomserver/internal/perform/perform_admin.go
+++ b/roomserver/internal/perform/perform_admin.go
@@ -77,6 +77,7 @@ func (r *Admin) PerformAdminEvacuateRoom(
 	}
 
 	inputEvents := make([]api.InputRoomEvent, 0, len(memberEvents))
+	res.Affected = make([]string, 0, len(memberEvents))
 	latestReq := &api.QueryLatestEventsAndStateRequest{
 		RoomID: req.RoomID,
 	}
@@ -144,6 +145,7 @@ func (r *Admin) PerformAdminEvacuateRoom(
 			Origin:       r.Cfg.Matrix.ServerName,
 			SendAsServer: string(r.Cfg.Matrix.ServerName),
 		})
+		res.Affected = append(res.Affected, stateKey)
 	}
 
 	inputReq := &api.InputRoomEventsRequest{