diff --git a/cli.py b/cli.py
index d02724e..0bdb4b5 100755
--- a/cli.py
+++ b/cli.py
@@ -53,7 +53,6 @@ if __name__ == '__main__':
         whitelist = set(args.whitelist.split())
 
     # modify whitelist based on arguments
-    whitelist.add(args.separator)
     if args.allow:
         whitelist = whitelist.union(set(args.allow))
     if args.disallow:
diff --git a/normalisename.py b/normalisename.py
index ff79bd1..d8720e7 100755
--- a/normalisename.py
+++ b/normalisename.py
@@ -27,7 +27,7 @@ class Normalisename:
 
     @property
     def whitelist(self):
-        return self._whitelist
+        return self._whitelist.union({self.separator})
 
     def __call__(self, files):
         for path in files: