diff --git a/src/eckit/option/FactoryOption.cc b/src/eckit/option/FactoryOption.cc
index 78dffaf74..8276eeee6 100644
--- a/src/eckit/option/FactoryOption.cc
+++ b/src/eckit/option/FactoryOption.cc
@@ -12,6 +12,8 @@
 /// @author Tiago Quintino
 /// @date Apr 2015
 
+#pragma once
+
 #include <iostream>
 
 #include "eckit/config/Configuration.h"
diff --git a/src/eckit/option/SimpleOption.cc b/src/eckit/option/SimpleOption.cc
index 9066eb77d..ea1bb4de3 100644
--- a/src/eckit/option/SimpleOption.cc
+++ b/src/eckit/option/SimpleOption.cc
@@ -12,6 +12,8 @@
 /// @author Tiago Quintino
 /// @date Apr 2015
 
+#pragma once
+
 #include <iostream>
 
 #include "eckit/config/Configuration.h"
diff --git a/src/eckit/option/VectorOption.cc b/src/eckit/option/VectorOption.cc
index 7144ac518..3f612568d 100644
--- a/src/eckit/option/VectorOption.cc
+++ b/src/eckit/option/VectorOption.cc
@@ -13,6 +13,8 @@
 /// @author Simon Smart
 /// @date March 2016
 
+#pragma once
+
 #include <iostream>
 
 #include "eckit/exception/Exceptions.h"