diff --git a/include/faker-cxx/types/Country.h b/include/faker-cxx/types/Country.h
index ca92b20ff..4de97bc4a 100644
--- a/include/faker-cxx/types/Country.h
+++ b/include/faker-cxx/types/Country.h
@@ -3,6 +3,7 @@
 #include <map>
 #include <string>
 #include <vector>
+#include <ostream>
 
 namespace faker
 {