diff --git a/docs/spec/v1beta1/provider.md b/docs/spec/v1beta1/provider.md
index b0745d4ae..4541678ef 100644
--- a/docs/spec/v1beta1/provider.md
+++ b/docs/spec/v1beta1/provider.md
@@ -333,6 +333,7 @@ The provider will send the following labels for the event.
 | ----------- | -------------------------------------------------------------------------------------------------- |
 | alertname   | The string Flux followed by the Kind and the reason for the event e.g FluxKustomizationProgressing |
 | severity    | The severity of the event (error|info)                                                             |
+| timestamp   | The timestamp of the event                                                                         |
 | reason      | The machine readable reason for the objects transition into the current status                     |
 | kind        | The kind of the involved object associated with the event                                          |
 | name        | The name of the involved object associated with the event                                          |
diff --git a/internal/notifier/alertmanager.go b/internal/notifier/alertmanager.go
index 0051b3184..efee975ff 100644
--- a/internal/notifier/alertmanager.go
+++ b/internal/notifier/alertmanager.go
@@ -72,6 +72,7 @@ func (s *Alertmanager) Post(event events.Event) error {
 	labels["alertname"] = "Flux" + event.InvolvedObject.Kind + strings.Title(event.Reason)
 	labels["severity"] = event.Severity
 	labels["reason"] = event.Reason
+	labels["timestamp"] = event.Timestamp.String()
 
 	labels["kind"] = event.InvolvedObject.Kind
 	labels["name"] = event.InvolvedObject.Name