diff --git a/openpilot/cereal/custom.capnp b/openpilot/cereal/custom.capnp
index 086b10c01c..cfbbbe472a 100644
--- a/openpilot/cereal/custom.capnp
+++ b/openpilot/cereal/custom.capnp
@@ -353,6 +353,7 @@ struct OnroadEventSP @0xda96579883444c35 {
     speedLimitPending @22;
     e2eChime @23;
     laneChangeRoadEdge @24;
+    bigModelReady @25;
   }
 }
 
diff --git a/openpilot/selfdrive/selfdrived/selfdrived.py b/openpilot/selfdrive/selfdrived/selfdrived.py
index 180b58c916..dfaa94e013 100755
--- a/openpilot/selfdrive/selfdrived/selfdrived.py
+++ b/openpilot/selfdrive/selfdrived/selfdrived.py
@@ -198,6 +198,7 @@ class SelfdriveD(CruiseHelper):
     loading = self.params.get_bool("ChestnutLoading")
     if self.big_model_loading and not loading:
       self.big_model_ready_t = time.monotonic()
+      self.events_sp.add(custom.OnroadEventSP.EventName.bigModelReady)
     self.big_model_loading = loading
     if self.big_model_loading:
       self.events.add(EventName.bigModelLoading)
diff --git a/openpilot/sunnypilot/selfdrive/selfdrived/events.py b/openpilot/sunnypilot/selfdrive/selfdrived/events.py
index 3c010cc776..b50873dea4 100644
--- a/openpilot/sunnypilot/selfdrive/selfdrived/events.py
+++ b/openpilot/sunnypilot/selfdrive/selfdrived/events.py
@@ -252,4 +252,12 @@ EVENTS_SP: dict[int, dict[str, Alert | AlertCallbackType]] = {
       AlertStatus.userPrompt, AlertSize.small,
       Priority.LOW, VisualAlert.none, AudibleAlert.prompt, 0.1),
   },
+
+  EventNameSP.bigModelReady: {
+    ET.PERMANENT: Alert(
+      "Big Model Ready",
+      "",
+      AlertStatus.normal, AlertSize.small,
+      Priority.LOW, VisualAlert.none, AudibleAlert.prompt, 2.),
+  },
 }