diff --git a/include/boost/unordered/detail/narrow_cast.hpp b/include/boost/unordered/detail/narrow_cast.hpp
index 8b1d8e1c..8fb7f304 100644
--- a/include/boost/unordered/detail/narrow_cast.hpp
+++ b/include/boost/unordered/detail/narrow_cast.hpp
@@ -19,7 +19,7 @@ namespace unordered{
 namespace detail{
 
 template<typename To,typename From>
-BOOST_CONSTEXPR To narrow_cast(From x) noexcept
+constexpr To narrow_cast(From x) noexcept
 {
   BOOST_STATIC_ASSERT(boost::is_integral<From>::value);
   BOOST_STATIC_ASSERT(boost::is_integral<To>::value);
diff --git a/include/boost/unordered/unordered_map.hpp b/include/boost/unordered/unordered_map.hpp
index d2bbbeb6..6dc3f625 100644
--- a/include/boost/unordered/unordered_map.hpp
+++ b/include/boost/unordered/unordered_map.hpp
@@ -2894,7 +2894,7 @@ namespace boost {
       }
 
     public:
-      BOOST_CONSTEXPR node_handle_map() noexcept : ptr_(), alloc_() {}
+      constexpr node_handle_map() noexcept : ptr_(), alloc_() {}
 
       ~node_handle_map()
       {
diff --git a/include/boost/unordered/unordered_set.hpp b/include/boost/unordered/unordered_set.hpp
index 9a28a865..cf226493 100644
--- a/include/boost/unordered/unordered_set.hpp
+++ b/include/boost/unordered/unordered_set.hpp
@@ -2251,7 +2251,7 @@ namespace boost {
       }
 
     public:
-      BOOST_CONSTEXPR node_handle_set() noexcept : ptr_(), has_alloc_(false) {}
+      constexpr node_handle_set() noexcept : ptr_(), has_alloc_(false) {}
 
       ~node_handle_set()
       {