diff --git a/include/matador/utils/convert.hpp b/include/matador/utils/convert.hpp
index a678965..0bacd9f 100644
--- a/include/matador/utils/convert.hpp
+++ b/include/matador/utils/convert.hpp
@@ -9,6 +9,7 @@
 #include <cstring>
 #include <iomanip>
 #include <string>
+#include <sstream>
 #include <type_traits>
 
 /*