diff --git a/mellon/views.py b/mellon/views.py
index 39aec16..7dfa785 100644
--- a/mellon/views.py
+++ b/mellon/views.py
@@ -659,6 +659,9 @@ class LogoutView(ProfileMixin, LogMixin, View):
                     if logout:
                         self.set_next_url(next_url)
                     self.log.info('user logged out, SLO request sent to IdP')
+            else:
+                # anonymous user: if next_url is None redirect to referer
+                return HttpResponseRedirect(next_url or referer)
         else:
             self.log.warning('logout refused referer %r is not of the same origin', referer)
         return HttpResponseRedirect(next_url)
diff --git a/tests/test_sso_slo.py b/tests/test_sso_slo.py
index d7f07b4..77532ab 100644
--- a/tests/test_sso_slo.py
+++ b/tests/test_sso_slo.py
@@ -233,8 +233,11 @@ def test_sso_slo(db, app, idp, caplog, sp_settings):
     assert 'created new user' in caplog.text
     assert 'logged in using SAML' in caplog.text
     assert urlparse.urlparse(response['Location']).path == '/whatever/'
-    response = app.get(reverse('mellon_logout'))
+    response = app.get(reverse('mellon_logout'), extra_environ={'HTTP_REFERER': str('/some/path')})
     assert urlparse.urlparse(response['Location']).path == '/singleLogout'
+    # again, user is already logged out
+    response = app.get(reverse('mellon_logout'), extra_environ={'HTTP_REFERER': str('/some/path')})
+    assert urlparse.urlparse(response['Location']).path == '/some/path'
 
 
 def test_sso_idp_slo(db, app, idp, caplog, sp_settings):