diff --git a/include/boost/unordered/unordered_map.hpp b/include/boost/unordered/unordered_map.hpp
index 7b2ff6fc..f40d03d4 100644
--- a/include/boost/unordered/unordered_map.hpp
+++ b/include/boost/unordered/unordered_map.hpp
@@ -729,6 +729,7 @@ template <class K, class T, class H, class P, class A> class unordered_map
         const key_type&) const;
 
     mapped_type& operator[](const key_type&);
+    mapped_type& operator[](BOOST_RV_REF(key_type));
     mapped_type& at(const key_type&);
     mapped_type const& at(const key_type&) const;
 
@@ -1627,6 +1628,13 @@ typename unordered_map<K, T, H, P, A>::mapped_type&
     return table_.try_emplace_impl(k).first->second;
 }
 
+template <class K, class T, class H, class P, class A>
+typename unordered_map<K, T, H, P, A>::mapped_type&
+    unordered_map<K, T, H, P, A>::operator[](BOOST_RV_REF(key_type) k)
+{
+    return table_.try_emplace_impl(boost::move(k)).first->second;
+}
+
 template <class K, class T, class H, class P, class A>
 typename unordered_map<K, T, H, P, A>::mapped_type&
 unordered_map<K, T, H, P, A>::at(const key_type& k)
diff --git a/test/unordered/compile_tests.hpp b/test/unordered/compile_tests.hpp
index c676f2d5..12759c16 100644
--- a/test/unordered/compile_tests.hpp
+++ b/test/unordered/compile_tests.hpp
@@ -422,6 +422,7 @@ void unordered_map_functions(X&, Key const& k, T const& v)
 
     X a;
     test::check_return_type<mapped_type>::equals_ref(a[k]);
+    test::check_return_type<mapped_type>::equals_ref(a[rvalue(k)]);
     test::check_return_type<mapped_type>::equals_ref(a.at(k));
     test::check_return_type<std::pair<iterator, bool> >::equals(
         a.try_emplace(k, v));