diff --git a/src/Boot/DrupalBoot8.php b/src/Boot/DrupalBoot8.php
index f4b174972d..058a52166f 100644
--- a/src/Boot/DrupalBoot8.php
+++ b/src/Boot/DrupalBoot8.php
@@ -141,7 +141,7 @@ public function bootstrapDrupalSiteValidate(BootstrapManager $manager)
 
         // Account for users who omit the http:// prefix.
         if (empty($parsed_url['scheme'])) {
-            $this->uri = 'http://' . $this->uri;
+            $this->uri = 'http://' . $uri;
             $parsed_url = parse_url($this->uri);
         }