diff --git a/lib/https/index.js b/lib/https/index.js
index 4b2386d18..95fd88b0f 100644
--- a/lib/https/index.js
+++ b/lib/https/index.js
@@ -747,7 +747,7 @@ function toHttp1(req, res) {
   options.protocol = null;
   options.hostname = null;
   options.agent = false;
-  options.host = config.host;
+  options.host = config.host || LOCALHOST;
   options.port = config.port;
   options.headers = headers;
   if (isH2) {