diff --git a/config/environments/production.rb b/config/environments/production.rb
index b5e7ed8f..a75ece3a 100644
--- a/config/environments/production.rb
+++ b/config/environments/production.rb
@@ -84,10 +84,10 @@
   config.active_record.dump_schema_after_migration = false
 
   # Enable DNS rebinding protection and other `Host` header attacks.
-  # config.hosts = [
-  #   "example.com",     # Allow requests from example.com
-  #   /.*\.example\.com/ # Allow requests from subdomains like `www.example.com`
-  # ]
+  config.hosts = [
+    /contacts-admin\..*gov.uk?/,
+  ]
+
   # Skip DNS rebinding protection for the default health check endpoint.
-  # config.host_authorization = { exclude: ->(request) { request.path == "/up" } }
+  config.host_authorization = { exclude: ->(request) { request.path.match?("^\/healthcheck") } }
 end