diff --git a/synapse/crypto/context_factory.py b/synapse/crypto/context_factory.py
index 08c41a92b6..1a391adec1 100644
--- a/synapse/crypto/context_factory.py
+++ b/synapse/crypto/context_factory.py
@@ -123,6 +123,6 @@ class ClientTLSOptionsFactory(object):
 
     def get_options(self, host):
         return ClientTLSOptions(
-            unicode(host),
+            host.decode('utf-8'),
             CertificateOptions(verify=False).getContext()
         )