diff --git a/src/cmd/go/internal/auth/auth.go b/src/cmd/go/internal/auth/auth.go
index 12e3c74dcc..fe5a89d727 100644
--- a/src/cmd/go/internal/auth/auth.go
+++ b/src/cmd/go/internal/auth/auth.go
@@ -10,10 +10,12 @@ import "net/http"
 // AddCredentials fills in the user's credentials for req, if any.
 // The return value reports whether any matching credentials were found.
 func AddCredentials(req *http.Request) (added bool) {
+	host := req.URL.Hostname()
+
 	// TODO(golang.org/issue/26232): Support arbitrary user-provided credentials.
 	netrcOnce.Do(readNetrc)
 	for _, l := range netrc {
-		if l.machine == req.URL.Host {
+		if l.machine == host {
 			req.SetBasicAuth(l.login, l.password)
 			return true
 		}