diff --git a/NEWS b/NEWS
index e7caa7cdb4e..7f52099e2e4 100644
--- a/NEWS
+++ b/NEWS
@@ -23,6 +23,10 @@ PHP                                                                        NEWS
 - MBstring:
   . Updated Unicode data tables to Unicode 17.0. (Yuya Hamada)
 
+- Standard:
+  . Passing strings which are not one byte long to ord() is now deprecated.
+    (Girgias)
+
 - URI:
   . Fixed bug GH-19780 (InvalidUrlException should check $errors argument).
     (nielsdos)
diff --git a/UPGRADING b/UPGRADING
index cc9524996fe..09675d91ee0 100644
--- a/UPGRADING
+++ b/UPGRADING
@@ -555,6 +555,9 @@ PHP 8.5 UPGRADE NOTES
   . Passing integers outside the interval [0, 255] to chr() is now deprecated.
     This is because a byte can only hold a value within this interval.
     RFC: https://wiki.php.net/rfc/deprecations_php_8_5#deprecate_passing_integers_outside_the_interval_0_255_to_chr
+  . Passing a string which is not a single byte to ord() is now deprecated,
+    this is indicative of a bug.
+    RFC: https://wiki.php.net/rfc/deprecations_php_8_5#deprecate_passing_string_which_are_not_one_byte_long_to_ord
   . Relying locally predefined variable $http_response_header is deprecated.
     Instead one should call the http_get_last_response_headers() function.
     RFC: https://wiki.php.net/rfc/deprecations_php_8_5#deprecate_the_http_response_header_predefined_variable