diff --git a/tgcf/plugins/filter.py b/tgcf/plugins/filter.py
index 1bf70b5e..39a87c2e 100644
--- a/tgcf/plugins/filter.py
+++ b/tgcf/plugins/filter.py
@@ -40,7 +40,7 @@ def __init__(self, data: Dict[str, Any]) -> None:
     def case_correct(self) -> None:
         textf: TextFilter = self.filters.text
 
-        if textf.case_sensitive is False:
+        if textf.case_sensitive is False and textf.regex is False:
             textf.blacklist = [item.lower() for item in textf.blacklist]
             textf.whitelist = [item.lower() for item in textf.whitelist]