diff --git a/change/react-native-windows-298c0d56-3472-45c2-a2e6-8d139481f19c.json b/change/react-native-windows-298c0d56-3472-45c2-a2e6-8d139481f19c.json
new file mode 100644
index 00000000000..f179e78fa8e
--- /dev/null
+++ b/change/react-native-windows-298c0d56-3472-45c2-a2e6-8d139481f19c.json
@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "Fix unintended fallthrough This was causing a WM_CHAR to fallthrough to WM_KEYDOWN and produce a duplicate `sendMessage`",
+  "packageName": "react-native-windows",
+  "email": "26607885+chrisglein@users.noreply.github.com",
+  "dependentChangeType": "patch"
+}
diff --git a/vnext/Microsoft.ReactNative/Fabric/Composition/CompositionEventHandler.cpp b/vnext/Microsoft.ReactNative/Fabric/Composition/CompositionEventHandler.cpp
index 704493dacbf..23a9cfb4b5d 100644
--- a/vnext/Microsoft.ReactNative/Fabric/Composition/CompositionEventHandler.cpp
+++ b/vnext/Microsoft.ReactNative/Fabric/Composition/CompositionEventHandler.cpp
@@ -164,6 +164,7 @@ int64_t CompositionEventHandler::SendMessage(uint32_t msg, uint64_t wParam, int6
         if (result)
           return result;
       }
+      break;
     }
     case WM_KEYDOWN:
     case WM_KEYUP: