diff --git a/include/boost/limits.hpp b/include/boost/limits.hpp
index 370c0f21..6d01daa3 100644
--- a/include/boost/limits.hpp
+++ b/include/boost/limits.hpp
@@ -30,6 +30,8 @@
 #  define BOOST_ULLT  ::boost::ulong_long_type
 #endif
 
+#include <climits>  // for CHAR_BIT
+
 namespace std
 {
   template<>