diff --git a/terraform/application/config/test.yml b/terraform/application/config/test.yml
index ed97d539c..c24638d80 100644
--- a/terraform/application/config/test.yml
+++ b/terraform/application/config/test.yml
@@ -1 +1,2 @@
 ---
+EXTERNAL_DOMAIN: test.refer-serious-misconduct.education.gov.uk