diff --git a/include/nlohmann/detail/macro_scope.hpp b/include/nlohmann/detail/macro_scope.hpp
index cd01039e4..2075ecf22 100644
--- a/include/nlohmann/detail/macro_scope.hpp
+++ b/include/nlohmann/detail/macro_scope.hpp
@@ -464,5 +464,5 @@
 #endif
 
 #ifndef JSON_USE_GLOBAL_UDLS
-    #define JSON_USE_GLOBAL_UDLS 0
+    #define JSON_USE_GLOBAL_UDLS 1
 #endif
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
index 8a8a0a0c7..79f3db941 100644
--- a/single_include/nlohmann/json.hpp
+++ b/single_include/nlohmann/json.hpp
@@ -2793,7 +2793,7 @@ JSON_HEDLEY_DIAGNOSTIC_POP
 #endif
 
 #ifndef JSON_USE_GLOBAL_UDLS
-    #define JSON_USE_GLOBAL_UDLS 0
+    #define JSON_USE_GLOBAL_UDLS 1
 #endif
 
 #if JSON_HAS_THREE_WAY_COMPARISON