diff --git a/logging/monolog_exclude_http_codes.rst b/logging/monolog_exclude_http_codes.rst
index c0bc4f92fa6..6e25828f622 100644
--- a/logging/monolog_exclude_http_codes.rst
+++ b/logging/monolog_exclude_http_codes.rst
@@ -59,3 +59,10 @@ logging these HTTP codes based on the MonologBundle configuration:
                 ],
             ],
         ]);
+
+.. caution::
+    Combining ``excluded_http_codes`` with a ``passthru_level`` lower than
+    ``error`` (i.e. ``debug``, ``info``, ``notice`` or ``warning``) will not
+    actually exclude log messages for those HTTP codes because they are logged
+    with level of ``error`` or higher and ``passthru_level`` takes precedence
+    over the HTTP codes being listed in ``excluded_http_codes``.