diff --git a/jwcrypto/jwt.py b/jwcrypto/jwt.py
index 27f1f0a..a6eeaf6 100644
--- a/jwcrypto/jwt.py
+++ b/jwcrypto/jwt.py
@@ -303,7 +303,7 @@ def _expected_type_heuristics(self, key=None):
             if set(self._algs).issubset(jwe_algs + ['RSA1_5']):
                 self._expected_type = "JWE"
             elif set(self._algs).issubset(jws_algs):
-                self._expected_type = "JES"
+                self._expected_type = "JWS"
         if self._expected_type is None and self._header:
             if "enc" in json_decode(self._header):
                 self._expected_type = "JWE"