diff --git a/pkg/services/ngalert/models/instance.go b/pkg/services/ngalert/models/instance.go
index 8f0c26affee..dd14f8a2bb4 100644
--- a/pkg/services/ngalert/models/instance.go
+++ b/pkg/services/ngalert/models/instance.go
@@ -39,6 +39,7 @@ func (i InstanceStateType) IsValid() bool {
 	return i == InstanceStateFiring ||
 		i == InstanceStateNormal ||
 		i == InstanceStateNoData ||
+		i == InstanceStatePending ||
 		i == InstanceStateError
 }