diff --git a/test_package/test_package.cpp b/test_package/test_package.cpp
index c6229ecf..15e159e0 100644
--- a/test_package/test_package.cpp
+++ b/test_package/test_package.cpp
@@ -34,7 +34,7 @@ import mp_units;
 #include <mp-units/ostream.h>
 #include <mp-units/systems/isq.h>
 #include <mp-units/systems/si.h>
-#include <iostream>
+#endif
 
 using namespace mp_units;