diff --git a/src/calibre/utils/icu.py b/src/calibre/utils/icu.py
index b3e2cba5b3..7d4042610a 100644
--- a/src/calibre/utils/icu.py
+++ b/src/calibre/utils/icu.py
@@ -97,7 +97,7 @@ def non_numeric_sort_collator():
     if _non_numeric_sort_collator is None:
         _non_numeric_sort_collator = collator().clone()
         _non_numeric_sort_collator.strength = _icu.UCOL_SECONDARY
-        _sort_collator.numeric = False
+        _non_numeric_sort_collator.numeric = False
     return _sort_collator