diff --git a/ebos/ecltransmissibility.hh b/ebos/ecltransmissibility.hh
index 03831d46e..e7aa09f56 100644
--- a/ebos/ecltransmissibility.hh
+++ b/ebos/ecltransmissibility.hh
@@ -39,6 +39,7 @@
 #include <vector>
 #include <unordered_map>
 #include <functional>
+#include <cstdint>
 
 namespace Opm {