diff --git a/django/http/response.py b/django/http/response.py
index 27d99a621d..b3f44cdf92 100644
--- a/django/http/response.py
+++ b/django/http/response.py
@@ -42,6 +42,7 @@ REASON_PHRASES = {
     305: 'USE PROXY',
     306: 'RESERVED',
     307: 'TEMPORARY REDIRECT',
+    308: 'PERMANENT REDIRECT',
     400: 'BAD REQUEST',
     401: 'UNAUTHORIZED',
     402: 'PAYMENT REQUIRED',