diff --git a/tools/server/server-models.cpp b/tools/server/server-models.cpp
index 4ac55cd158..62dae2db7a 100644
--- a/tools/server/server-models.cpp
+++ b/tools/server/server-models.cpp
@@ -1181,7 +1181,8 @@ server_http_proxy::server_http_proxy(
                 continue;
             }
             if (key == "Host" || key == "host") {
-                req.set_header(key, host);
+                bool is_default_port = (scheme == "https" && port == 443) || (scheme == "http" && port == 80);
+                req.set_header(key, is_default_port ? host : host + ":" + std::to_string(port));
             } else {
                 req.set_header(key, value);
             }