diff --git a/actionpack/CHANGELOG.md b/actionpack/CHANGELOG.md
index 0ffae5086e80281162a2b200b12e96833fd01112..72121668acd64d8ce87fc8eae12af017327459e1 100644
--- a/actionpack/CHANGELOG.md
+++ b/actionpack/CHANGELOG.md
@@ -1,5 +1,9 @@
 ## Rails 4.0.0 (unreleased) ##
 
+*   Clear url helpers when reloading routes.
+
+    *Santiago Pastorino*
+
 *   `BestStandardsSupport` middleware now appends it's `X-UA-Compatible` value to app's
     returned value if any. Fix #8086
 
diff --git a/actionpack/lib/action_dispatch/routing/route_set.rb b/actionpack/lib/action_dispatch/routing/route_set.rb
index 61071d1228b4f0f89e409d5df7bb318ee902740e..0f95daa790e5abd4b19171dc26a2638126c61102 100644
--- a/actionpack/lib/action_dispatch/routing/route_set.rb
+++ b/actionpack/lib/action_dispatch/routing/route_set.rb
@@ -288,6 +288,7 @@ def finalize!
 
       def clear!
         @finalized = false
+        @url_helpers = nil
         named_routes.clear
         set.clear
         formatter.clear