diff --git a/Lib/ntpath.py b/Lib/ntpath.py
index 4b78d8d..ac928e1 100644
--- a/Lib/ntpath.py
+++ b/Lib/ntpath.py
@@ -257,7 +257,7 @@
 def ismount(path):
     """Test whether a path is a mount point (defined as root of drive)"""
     unc, rest = splitunc(path)
-    seps = _get_bothseps(p)
+    seps = _get_bothseps(path)
     if unc:
         return rest in p[:0] + seps
     p = splitdrive(path)[1]
diff --git a/Misc/NEWS b/Misc/NEWS
index c6f9594..9422ef1 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -43,6 +43,8 @@
 Library
 -------
 
+- Issue #5595: Fix UnboundedLocalError in ntpath.ismount().
+
 - Issue #1174606: Calling read() without arguments of an unbounded file
   (typically /dev/zero under Unix) could crash the interpreter.