diff --git a/include/internal/catch_approx.hpp b/include/internal/catch_approx.hpp
index 9d6cb9f8..590c8f5b 100644
--- a/include/internal/catch_approx.hpp
+++ b/include/internal/catch_approx.hpp
@@ -10,6 +10,7 @@
 
 #include "catch_tostring.h"
 
+#include <algorithm>
 #include <cmath>
 
 #include <type_traits>