diff --git a/Lib/smtplib.py b/Lib/smtplib.py
index e1651c0a8bcf1c..0c6106543240a6 100755
--- a/Lib/smtplib.py
+++ b/Lib/smtplib.py
@@ -255,6 +255,7 @@ def __init__(self, host='', port=0, local_hostname=None,
         if host:
             (code, msg) = self.connect(host, port)
             if code != 220:
+                self.close()
                 raise SMTPConnectError(code, msg)
         if local_hostname is not None:
             self.local_hostname = local_hostname