diff --git a/Core/include/Acts/Fitter/KalmanFitter.hpp b/Core/include/Acts/Fitter/KalmanFitter.hpp
index c2cbf99df6bafc741507926b268b2a2bce43c2f1..e55c4a94492ff97c63661f53f806ac0af29e4c91 100644
--- a/Core/include/Acts/Fitter/KalmanFitter.hpp
+++ b/Core/include/Acts/Fitter/KalmanFitter.hpp
@@ -8,8 +8,6 @@
 
 #pragma once
 
-#include <functional>
-#include <memory>
 #include "Acts/EventData/Measurement.hpp"
 #include "Acts/EventData/MeasurementHelpers.hpp"
 #include "Acts/EventData/MultiTrajectory.hpp"
@@ -30,6 +28,10 @@
 #include "Acts/Utilities/Logger.hpp"
 #include "Acts/Utilities/Result.hpp"
 
+#include <functional>
+#include <map>
+#include <memory>
+
 namespace Acts {
 
 /// @brief Options struct how the Fitter is called