diff --git a/api/server/auth/auth.go b/api/server/auth/auth.go
index 186e71c7..ad75a93d 100644
--- a/api/server/auth/auth.go
+++ b/api/server/auth/auth.go
@@ -102,9 +102,10 @@ func (h authHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 
 func namespaceFromRequest(req *http.Request) (string, error) {
 	// determine the host, e.g. dev.micro.mu:8080
-	host := req.URL.Host
+	host := req.URL.Hostname()
 	if len(host) == 0 {
-		host = req.Host
+		// fallback to req.Host
+		host, _, _ = net.SplitHostPort(req.Host)
 	}
 
 	// check for an ip address
@@ -112,12 +113,6 @@ func namespaceFromRequest(req *http.Request) (string, error) {
 		return auth.DefaultNamespace, nil
 	}
 
-	// split the host to remove the port
-	host, _, err := net.SplitHostPort(req.Host)
-	if err != nil {
-		return "", err
-	}
-
 	// check for dev enviroment
 	if host == "localhost" || host == "127.0.0.1" {
 		return auth.DefaultNamespace, nil